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Diffstat (limited to 'src/backend/utils/adt/ruleutils.c')
| -rw-r--r-- | src/backend/utils/adt/ruleutils.c | 12131 |
1 files changed, 12131 insertions, 0 deletions
diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c new file mode 100644 index 0000000..5d83953 --- /dev/null +++ b/src/backend/utils/adt/ruleutils.c @@ -0,0 +1,12131 @@ +/*------------------------------------------------------------------------- + * + * ruleutils.c + * Functions to convert stored expressions/querytrees back to + * source text + * + * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/backend/utils/adt/ruleutils.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include <ctype.h> +#include <unistd.h> +#include <fcntl.h> + +#include "access/amapi.h" +#include "access/htup_details.h" +#include "access/relation.h" +#include "access/sysattr.h" +#include "access/table.h" +#include "catalog/pg_aggregate.h" +#include "catalog/pg_am.h" +#include "catalog/pg_authid.h" +#include "catalog/pg_collation.h" +#include "catalog/pg_constraint.h" +#include "catalog/pg_depend.h" +#include "catalog/pg_language.h" +#include "catalog/pg_opclass.h" +#include "catalog/pg_operator.h" +#include "catalog/pg_partitioned_table.h" +#include "catalog/pg_proc.h" +#include "catalog/pg_statistic_ext.h" +#include "catalog/pg_trigger.h" +#include "catalog/pg_type.h" +#include "commands/defrem.h" +#include "commands/tablespace.h" +#include "common/keywords.h" +#include "executor/spi.h" +#include "funcapi.h" +#include "mb/pg_wchar.h" +#include "miscadmin.h" +#include "nodes/makefuncs.h" +#include "nodes/nodeFuncs.h" +#include "nodes/pathnodes.h" +#include "optimizer/optimizer.h" +#include "parser/parse_agg.h" +#include "parser/parse_func.h" +#include "parser/parse_node.h" +#include "parser/parse_oper.h" +#include "parser/parse_relation.h" +#include "parser/parser.h" +#include "parser/parsetree.h" +#include "rewrite/rewriteHandler.h" +#include "rewrite/rewriteManip.h" +#include "rewrite/rewriteSupport.h" +#include "utils/array.h" +#include "utils/builtins.h" +#include "utils/fmgroids.h" +#include "utils/guc.h" +#include "utils/hsearch.h" +#include "utils/lsyscache.h" +#include "utils/partcache.h" +#include "utils/rel.h" +#include "utils/ruleutils.h" +#include "utils/snapmgr.h" +#include "utils/syscache.h" +#include "utils/typcache.h" +#include "utils/varlena.h" +#include "utils/xml.h" + +/* ---------- + * Pretty formatting constants + * ---------- + */ + +/* Indent counts */ +#define PRETTYINDENT_STD 8 +#define PRETTYINDENT_JOIN 4 +#define PRETTYINDENT_VAR 4 + +#define PRETTYINDENT_LIMIT 40 /* wrap limit */ + +/* Pretty flags */ +#define PRETTYFLAG_PAREN 0x0001 +#define PRETTYFLAG_INDENT 0x0002 +#define PRETTYFLAG_SCHEMA 0x0004 + +/* Default line length for pretty-print wrapping: 0 means wrap always */ +#define WRAP_COLUMN_DEFAULT 0 + +/* macros to test if pretty action needed */ +#define PRETTY_PAREN(context) ((context)->prettyFlags & PRETTYFLAG_PAREN) +#define PRETTY_INDENT(context) ((context)->prettyFlags & PRETTYFLAG_INDENT) +#define PRETTY_SCHEMA(context) ((context)->prettyFlags & PRETTYFLAG_SCHEMA) + + +/* ---------- + * Local data types + * ---------- + */ + +/* Context info needed for invoking a recursive querytree display routine */ +typedef struct +{ + StringInfo buf; /* output buffer to append to */ + List *namespaces; /* List of deparse_namespace nodes */ + List *windowClause; /* Current query level's WINDOW clause */ + List *windowTList; /* targetlist for resolving WINDOW clause */ + int prettyFlags; /* enabling of pretty-print functions */ + int wrapColumn; /* max line length, or -1 for no limit */ + int indentLevel; /* current indent level for pretty-print */ + bool varprefix; /* true to print prefixes on Vars */ + ParseExprKind special_exprkind; /* set only for exprkinds needing special + * handling */ + Bitmapset *appendparents; /* if not null, map child Vars of these relids + * back to the parent rel */ +} deparse_context; + +/* + * Each level of query context around a subtree needs a level of Var namespace. + * A Var having varlevelsup=N refers to the N'th item (counting from 0) in + * the current context's namespaces list. + * + * rtable is the list of actual RTEs from the Query or PlannedStmt. + * rtable_names holds the alias name to be used for each RTE (either a C + * string, or NULL for nameless RTEs such as unnamed joins). + * rtable_columns holds the column alias names to be used for each RTE. + * + * subplans is a list of Plan trees for SubPlans and CTEs (it's only used + * in the PlannedStmt case). + * ctes is a list of CommonTableExpr nodes (only used in the Query case). + * appendrels, if not null (it's only used in the PlannedStmt case), is an + * array of AppendRelInfo nodes, indexed by child relid. We use that to map + * child-table Vars to their inheritance parents. + * + * In some cases we need to make names of merged JOIN USING columns unique + * across the whole query, not only per-RTE. If so, unique_using is true + * and using_names is a list of C strings representing names already assigned + * to USING columns. + * + * When deparsing plan trees, there is always just a single item in the + * deparse_namespace list (since a plan tree never contains Vars with + * varlevelsup > 0). We store the Plan node that is the immediate + * parent of the expression to be deparsed, as well as a list of that + * Plan's ancestors. In addition, we store its outer and inner subplan nodes, + * as well as their targetlists, and the index tlist if the current plan node + * might contain INDEX_VAR Vars. (These fields could be derived on-the-fly + * from the current Plan node, but it seems notationally clearer to set them + * up as separate fields.) + */ +typedef struct +{ + List *rtable; /* List of RangeTblEntry nodes */ + List *rtable_names; /* Parallel list of names for RTEs */ + List *rtable_columns; /* Parallel list of deparse_columns structs */ + List *subplans; /* List of Plan trees for SubPlans */ + List *ctes; /* List of CommonTableExpr nodes */ + AppendRelInfo **appendrels; /* Array of AppendRelInfo nodes, or NULL */ + /* Workspace for column alias assignment: */ + bool unique_using; /* Are we making USING names globally unique */ + List *using_names; /* List of assigned names for USING columns */ + /* Remaining fields are used only when deparsing a Plan tree: */ + Plan *plan; /* immediate parent of current expression */ + List *ancestors; /* ancestors of plan */ + Plan *outer_plan; /* outer subnode, or NULL if none */ + Plan *inner_plan; /* inner subnode, or NULL if none */ + List *outer_tlist; /* referent for OUTER_VAR Vars */ + List *inner_tlist; /* referent for INNER_VAR Vars */ + List *index_tlist; /* referent for INDEX_VAR Vars */ + /* Special namespace representing a function signature: */ + char *funcname; + int numargs; + char **argnames; +} deparse_namespace; + +/* + * Per-relation data about column alias names. + * + * Selecting aliases is unreasonably complicated because of the need to dump + * rules/views whose underlying tables may have had columns added, deleted, or + * renamed since the query was parsed. We must nonetheless print the rule/view + * in a form that can be reloaded and will produce the same results as before. + * + * For each RTE used in the query, we must assign column aliases that are + * unique within that RTE. SQL does not require this of the original query, + * but due to factors such as *-expansion we need to be able to uniquely + * reference every column in a decompiled query. As long as we qualify all + * column references, per-RTE uniqueness is sufficient for that. + * + * However, we can't ensure per-column name uniqueness for unnamed join RTEs, + * since they just inherit column names from their input RTEs, and we can't + * rename the columns at the join level. Most of the time this isn't an issue + * because we don't need to reference the join's output columns as such; we + * can reference the input columns instead. That approach can fail for merged + * JOIN USING columns, however, so when we have one of those in an unnamed + * join, we have to make that column's alias globally unique across the whole + * query to ensure it can be referenced unambiguously. + * + * Another problem is that a JOIN USING clause requires the columns to be + * merged to have the same aliases in both input RTEs, and that no other + * columns in those RTEs or their children conflict with the USING names. + * To handle that, we do USING-column alias assignment in a recursive + * traversal of the query's jointree. When descending through a JOIN with + * USING, we preassign the USING column names to the child columns, overriding + * other rules for column alias assignment. We also mark each RTE with a list + * of all USING column names selected for joins containing that RTE, so that + * when we assign other columns' aliases later, we can avoid conflicts. + * + * Another problem is that if a JOIN's input tables have had columns added or + * deleted since the query was parsed, we must generate a column alias list + * for the join that matches the current set of input columns --- otherwise, a + * change in the number of columns in the left input would throw off matching + * of aliases to columns of the right input. Thus, positions in the printable + * column alias list are not necessarily one-for-one with varattnos of the + * JOIN, so we need a separate new_colnames[] array for printing purposes. + */ +typedef struct +{ + /* + * colnames is an array containing column aliases to use for columns that + * existed when the query was parsed. Dropped columns have NULL entries. + * This array can be directly indexed by varattno to get a Var's name. + * + * Non-NULL entries are guaranteed unique within the RTE, *except* when + * this is for an unnamed JOIN RTE. In that case we merely copy up names + * from the two input RTEs. + * + * During the recursive descent in set_using_names(), forcible assignment + * of a child RTE's column name is represented by pre-setting that element + * of the child's colnames array. So at that stage, NULL entries in this + * array just mean that no name has been preassigned, not necessarily that + * the column is dropped. + */ + int num_cols; /* length of colnames[] array */ + char **colnames; /* array of C strings and NULLs */ + + /* + * new_colnames is an array containing column aliases to use for columns + * that would exist if the query was re-parsed against the current + * definitions of its base tables. This is what to print as the column + * alias list for the RTE. This array does not include dropped columns, + * but it will include columns added since original parsing. Indexes in + * it therefore have little to do with current varattno values. As above, + * entries are unique unless this is for an unnamed JOIN RTE. (In such an + * RTE, we never actually print this array, but we must compute it anyway + * for possible use in computing column names of upper joins.) The + * parallel array is_new_col marks which of these columns are new since + * original parsing. Entries with is_new_col false must match the + * non-NULL colnames entries one-for-one. + */ + int num_new_cols; /* length of new_colnames[] array */ + char **new_colnames; /* array of C strings */ + bool *is_new_col; /* array of bool flags */ + + /* This flag tells whether we should actually print a column alias list */ + bool printaliases; + + /* This list has all names used as USING names in joins above this RTE */ + List *parentUsing; /* names assigned to parent merged columns */ + + /* + * If this struct is for a JOIN RTE, we fill these fields during the + * set_using_names() pass to describe its relationship to its child RTEs. + * + * leftattnos and rightattnos are arrays with one entry per existing + * output column of the join (hence, indexable by join varattno). For a + * simple reference to a column of the left child, leftattnos[i] is the + * child RTE's attno and rightattnos[i] is zero; and conversely for a + * column of the right child. But for merged columns produced by JOIN + * USING/NATURAL JOIN, both leftattnos[i] and rightattnos[i] are nonzero. + * Note that a simple reference might be to a child RTE column that's been + * dropped; but that's OK since the column could not be used in the query. + * + * If it's a JOIN USING, usingNames holds the alias names selected for the + * merged columns (these might be different from the original USING list, + * if we had to modify names to achieve uniqueness). + */ + int leftrti; /* rangetable index of left child */ + int rightrti; /* rangetable index of right child */ + int *leftattnos; /* left-child varattnos of join cols, or 0 */ + int *rightattnos; /* right-child varattnos of join cols, or 0 */ + List *usingNames; /* names assigned to merged columns */ +} deparse_columns; + +/* This macro is analogous to rt_fetch(), but for deparse_columns structs */ +#define deparse_columns_fetch(rangetable_index, dpns) \ + ((deparse_columns *) list_nth((dpns)->rtable_columns, (rangetable_index)-1)) + +/* + * Entry in set_rtable_names' hash table + */ +typedef struct +{ + char name[NAMEDATALEN]; /* Hash key --- must be first */ + int counter; /* Largest addition used so far for name */ +} NameHashEntry; + +/* Callback signature for resolve_special_varno() */ +typedef void (*rsv_callback) (Node *node, deparse_context *context, + void *callback_arg); + + +/* ---------- + * Global data + * ---------- + */ +static SPIPlanPtr plan_getrulebyoid = NULL; +static const char *query_getrulebyoid = "SELECT * FROM pg_catalog.pg_rewrite WHERE oid = $1"; +static SPIPlanPtr plan_getviewrule = NULL; +static const char *query_getviewrule = "SELECT * FROM pg_catalog.pg_rewrite WHERE ev_class = $1 AND rulename = $2"; + +/* GUC parameters */ +bool quote_all_identifiers = false; + + +/* ---------- + * Local functions + * + * Most of these functions used to use fixed-size buffers to build their + * results. Now, they take an (already initialized) StringInfo object + * as a parameter, and append their text output to its contents. + * ---------- + */ +static char *deparse_expression_pretty(Node *expr, List *dpcontext, + bool forceprefix, bool showimplicit, + int prettyFlags, int startIndent); +static char *pg_get_viewdef_worker(Oid viewoid, + int prettyFlags, int wrapColumn); +static char *pg_get_triggerdef_worker(Oid trigid, bool pretty); +static int decompile_column_index_array(Datum column_index_array, Oid relId, + StringInfo buf); +static char *pg_get_ruledef_worker(Oid ruleoid, int prettyFlags); +static char *pg_get_indexdef_worker(Oid indexrelid, int colno, + const Oid *excludeOps, + bool attrsOnly, bool keysOnly, + bool showTblSpc, bool inherits, + int prettyFlags, bool missing_ok); +static char *pg_get_statisticsobj_worker(Oid statextid, bool columns_only, + bool missing_ok); +static char *pg_get_partkeydef_worker(Oid relid, int prettyFlags, + bool attrsOnly, bool missing_ok); +static char *pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, + int prettyFlags, bool missing_ok); +static text *pg_get_expr_worker(text *expr, Oid relid, const char *relname, + int prettyFlags); +static int print_function_arguments(StringInfo buf, HeapTuple proctup, + bool print_table_args, bool print_defaults); +static void print_function_rettype(StringInfo buf, HeapTuple proctup); +static void print_function_trftypes(StringInfo buf, HeapTuple proctup); +static void print_function_sqlbody(StringInfo buf, HeapTuple proctup); +static void set_rtable_names(deparse_namespace *dpns, List *parent_namespaces, + Bitmapset *rels_used); +static void set_deparse_for_query(deparse_namespace *dpns, Query *query, + List *parent_namespaces); +static void set_simple_column_names(deparse_namespace *dpns); +static bool has_dangerous_join_using(deparse_namespace *dpns, Node *jtnode); +static void set_using_names(deparse_namespace *dpns, Node *jtnode, + List *parentUsing); +static void set_relation_column_names(deparse_namespace *dpns, + RangeTblEntry *rte, + deparse_columns *colinfo); +static void set_join_column_names(deparse_namespace *dpns, RangeTblEntry *rte, + deparse_columns *colinfo); +static bool colname_is_unique(const char *colname, deparse_namespace *dpns, + deparse_columns *colinfo); +static char *make_colname_unique(char *colname, deparse_namespace *dpns, + deparse_columns *colinfo); +static void expand_colnames_array_to(deparse_columns *colinfo, int n); +static void identify_join_columns(JoinExpr *j, RangeTblEntry *jrte, + deparse_columns *colinfo); +static char *get_rtable_name(int rtindex, deparse_context *context); +static void set_deparse_plan(deparse_namespace *dpns, Plan *plan); +static Plan *find_recursive_union(deparse_namespace *dpns, + WorkTableScan *wtscan); +static void push_child_plan(deparse_namespace *dpns, Plan *plan, + deparse_namespace *save_dpns); +static void pop_child_plan(deparse_namespace *dpns, + deparse_namespace *save_dpns); +static void push_ancestor_plan(deparse_namespace *dpns, ListCell *ancestor_cell, + deparse_namespace *save_dpns); +static void pop_ancestor_plan(deparse_namespace *dpns, + deparse_namespace *save_dpns); +static void make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc, + int prettyFlags); +static void make_viewdef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc, + int prettyFlags, int wrapColumn); +static void get_query_def(Query *query, StringInfo buf, List *parentnamespace, + TupleDesc resultDesc, bool colNamesVisible, + int prettyFlags, int wrapColumn, int startIndent); +static void get_values_def(List *values_lists, deparse_context *context); +static void get_with_clause(Query *query, deparse_context *context); +static void get_select_query_def(Query *query, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible); +static void get_insert_query_def(Query *query, deparse_context *context, + bool colNamesVisible); +static void get_update_query_def(Query *query, deparse_context *context, + bool colNamesVisible); +static void get_update_query_targetlist_def(Query *query, List *targetList, + deparse_context *context, + RangeTblEntry *rte); +static void get_delete_query_def(Query *query, deparse_context *context, + bool colNamesVisible); +static void get_utility_query_def(Query *query, deparse_context *context); +static void get_basic_select_query(Query *query, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible); +static void get_target_list(List *targetList, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible); +static void get_setop_query(Node *setOp, Query *query, + deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible); +static Node *get_rule_sortgroupclause(Index ref, List *tlist, + bool force_colno, + deparse_context *context); +static void get_rule_groupingset(GroupingSet *gset, List *targetlist, + bool omit_parens, deparse_context *context); +static void get_rule_orderby(List *orderList, List *targetList, + bool force_colno, deparse_context *context); +static void get_rule_windowclause(Query *query, deparse_context *context); +static void get_rule_windowspec(WindowClause *wc, List *targetList, + deparse_context *context); +static char *get_variable(Var *var, int levelsup, bool istoplevel, + deparse_context *context); +static void get_special_variable(Node *node, deparse_context *context, + void *callback_arg); +static void resolve_special_varno(Node *node, deparse_context *context, + rsv_callback callback, void *callback_arg); +static Node *find_param_referent(Param *param, deparse_context *context, + deparse_namespace **dpns_p, ListCell **ancestor_cell_p); +static void get_parameter(Param *param, deparse_context *context); +static const char *get_simple_binary_op_name(OpExpr *expr); +static bool isSimpleNode(Node *node, Node *parentNode, int prettyFlags); +static void appendContextKeyword(deparse_context *context, const char *str, + int indentBefore, int indentAfter, int indentPlus); +static void removeStringInfoSpaces(StringInfo str); +static void get_rule_expr(Node *node, deparse_context *context, + bool showimplicit); +static void get_rule_expr_toplevel(Node *node, deparse_context *context, + bool showimplicit); +static void get_rule_list_toplevel(List *lst, deparse_context *context, + bool showimplicit); +static void get_rule_expr_funccall(Node *node, deparse_context *context, + bool showimplicit); +static bool looks_like_function(Node *node); +static void get_oper_expr(OpExpr *expr, deparse_context *context); +static void get_func_expr(FuncExpr *expr, deparse_context *context, + bool showimplicit); +static void get_agg_expr(Aggref *aggref, deparse_context *context, + Aggref *original_aggref); +static void get_agg_combine_expr(Node *node, deparse_context *context, + void *callback_arg); +static void get_windowfunc_expr(WindowFunc *wfunc, deparse_context *context); +static bool get_func_sql_syntax(FuncExpr *expr, deparse_context *context); +static void get_coercion_expr(Node *arg, deparse_context *context, + Oid resulttype, int32 resulttypmod, + Node *parentNode); +static void get_const_expr(Const *constval, deparse_context *context, + int showtype); +static void get_const_collation(Const *constval, deparse_context *context); +static void simple_quote_literal(StringInfo buf, const char *val); +static void get_sublink_expr(SubLink *sublink, deparse_context *context); +static void get_tablefunc(TableFunc *tf, deparse_context *context, + bool showimplicit); +static void get_from_clause(Query *query, const char *prefix, + deparse_context *context); +static void get_from_clause_item(Node *jtnode, Query *query, + deparse_context *context); +static void get_column_alias_list(deparse_columns *colinfo, + deparse_context *context); +static void get_from_clause_coldeflist(RangeTblFunction *rtfunc, + deparse_columns *colinfo, + deparse_context *context); +static void get_tablesample_def(TableSampleClause *tablesample, + deparse_context *context); +static void get_opclass_name(Oid opclass, Oid actual_datatype, + StringInfo buf); +static Node *processIndirection(Node *node, deparse_context *context); +static void printSubscripts(SubscriptingRef *sbsref, deparse_context *context); +static char *get_relation_name(Oid relid); +static char *generate_relation_name(Oid relid, List *namespaces); +static char *generate_qualified_relation_name(Oid relid); +static char *generate_function_name(Oid funcid, int nargs, + List *argnames, Oid *argtypes, + bool has_variadic, bool *use_variadic_p, + ParseExprKind special_exprkind); +static char *generate_operator_name(Oid operid, Oid arg1, Oid arg2); +static void add_cast_to(StringInfo buf, Oid typid); +static char *generate_qualified_type_name(Oid typid); +static text *string_to_text(char *str); +static char *flatten_reloptions(Oid relid); +static void get_reloptions(StringInfo buf, Datum reloptions); + +#define only_marker(rte) ((rte)->inh ? "" : "ONLY ") + + +/* ---------- + * pg_get_ruledef - Do it all and return a text + * that could be used as a statement + * to recreate the rule + * ---------- + */ +Datum +pg_get_ruledef(PG_FUNCTION_ARGS) +{ + Oid ruleoid = PG_GETARG_OID(0); + int prettyFlags; + char *res; + + prettyFlags = PRETTYFLAG_INDENT; + + res = pg_get_ruledef_worker(ruleoid, prettyFlags); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + + +Datum +pg_get_ruledef_ext(PG_FUNCTION_ARGS) +{ + Oid ruleoid = PG_GETARG_OID(0); + bool pretty = PG_GETARG_BOOL(1); + int prettyFlags; + char *res; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + res = pg_get_ruledef_worker(ruleoid, prettyFlags); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + + +static char * +pg_get_ruledef_worker(Oid ruleoid, int prettyFlags) +{ + Datum args[1]; + char nulls[1]; + int spirc; + HeapTuple ruletup; + TupleDesc rulettc; + StringInfoData buf; + + /* + * Do this first so that string is alloc'd in outer context not SPI's. + */ + initStringInfo(&buf); + + /* + * Connect to SPI manager + */ + if (SPI_connect() != SPI_OK_CONNECT) + elog(ERROR, "SPI_connect failed"); + + /* + * On the first call prepare the plan to lookup pg_rewrite. We read + * pg_rewrite over the SPI manager instead of using the syscache to be + * checked for read access on pg_rewrite. + */ + if (plan_getrulebyoid == NULL) + { + Oid argtypes[1]; + SPIPlanPtr plan; + + argtypes[0] = OIDOID; + plan = SPI_prepare(query_getrulebyoid, 1, argtypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare failed for \"%s\"", query_getrulebyoid); + SPI_keepplan(plan); + plan_getrulebyoid = plan; + } + + /* + * Get the pg_rewrite tuple for this rule + */ + args[0] = ObjectIdGetDatum(ruleoid); + nulls[0] = ' '; + spirc = SPI_execute_plan(plan_getrulebyoid, args, nulls, true, 0); + if (spirc != SPI_OK_SELECT) + elog(ERROR, "failed to get pg_rewrite tuple for rule %u", ruleoid); + if (SPI_processed != 1) + { + /* + * There is no tuple data available here, just keep the output buffer + * empty. + */ + } + else + { + /* + * Get the rule's definition and put it into executor's memory + */ + ruletup = SPI_tuptable->vals[0]; + rulettc = SPI_tuptable->tupdesc; + make_ruledef(&buf, ruletup, rulettc, prettyFlags); + } + + /* + * Disconnect from SPI manager + */ + if (SPI_finish() != SPI_OK_FINISH) + elog(ERROR, "SPI_finish failed"); + + if (buf.len == 0) + return NULL; + + return buf.data; +} + + +/* ---------- + * pg_get_viewdef - Mainly the same thing, but we + * only return the SELECT part of a view + * ---------- + */ +Datum +pg_get_viewdef(PG_FUNCTION_ARGS) +{ + /* By OID */ + Oid viewoid = PG_GETARG_OID(0); + int prettyFlags; + char *res; + + prettyFlags = PRETTYFLAG_INDENT; + + res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + + +Datum +pg_get_viewdef_ext(PG_FUNCTION_ARGS) +{ + /* By OID */ + Oid viewoid = PG_GETARG_OID(0); + bool pretty = PG_GETARG_BOOL(1); + int prettyFlags; + char *res; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +Datum +pg_get_viewdef_wrap(PG_FUNCTION_ARGS) +{ + /* By OID */ + Oid viewoid = PG_GETARG_OID(0); + int wrap = PG_GETARG_INT32(1); + int prettyFlags; + char *res; + + /* calling this implies we want pretty printing */ + prettyFlags = PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA; + + res = pg_get_viewdef_worker(viewoid, prettyFlags, wrap); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +Datum +pg_get_viewdef_name(PG_FUNCTION_ARGS) +{ + /* By qualified name */ + text *viewname = PG_GETARG_TEXT_PP(0); + int prettyFlags; + RangeVar *viewrel; + Oid viewoid; + char *res; + + prettyFlags = PRETTYFLAG_INDENT; + + /* Look up view name. Can't lock it - we might not have privileges. */ + viewrel = makeRangeVarFromNameList(textToQualifiedNameList(viewname)); + viewoid = RangeVarGetRelid(viewrel, NoLock, false); + + res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + + +Datum +pg_get_viewdef_name_ext(PG_FUNCTION_ARGS) +{ + /* By qualified name */ + text *viewname = PG_GETARG_TEXT_PP(0); + bool pretty = PG_GETARG_BOOL(1); + int prettyFlags; + RangeVar *viewrel; + Oid viewoid; + char *res; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + /* Look up view name. Can't lock it - we might not have privileges. */ + viewrel = makeRangeVarFromNameList(textToQualifiedNameList(viewname)); + viewoid = RangeVarGetRelid(viewrel, NoLock, false); + + res = pg_get_viewdef_worker(viewoid, prettyFlags, WRAP_COLUMN_DEFAULT); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* + * Common code for by-OID and by-name variants of pg_get_viewdef + */ +static char * +pg_get_viewdef_worker(Oid viewoid, int prettyFlags, int wrapColumn) +{ + Datum args[2]; + char nulls[2]; + int spirc; + HeapTuple ruletup; + TupleDesc rulettc; + StringInfoData buf; + + /* + * Do this first so that string is alloc'd in outer context not SPI's. + */ + initStringInfo(&buf); + + /* + * Connect to SPI manager + */ + if (SPI_connect() != SPI_OK_CONNECT) + elog(ERROR, "SPI_connect failed"); + + /* + * On the first call prepare the plan to lookup pg_rewrite. We read + * pg_rewrite over the SPI manager instead of using the syscache to be + * checked for read access on pg_rewrite. + */ + if (plan_getviewrule == NULL) + { + Oid argtypes[2]; + SPIPlanPtr plan; + + argtypes[0] = OIDOID; + argtypes[1] = NAMEOID; + plan = SPI_prepare(query_getviewrule, 2, argtypes); + if (plan == NULL) + elog(ERROR, "SPI_prepare failed for \"%s\"", query_getviewrule); + SPI_keepplan(plan); + plan_getviewrule = plan; + } + + /* + * Get the pg_rewrite tuple for the view's SELECT rule + */ + args[0] = ObjectIdGetDatum(viewoid); + args[1] = DirectFunctionCall1(namein, CStringGetDatum(ViewSelectRuleName)); + nulls[0] = ' '; + nulls[1] = ' '; + spirc = SPI_execute_plan(plan_getviewrule, args, nulls, true, 0); + if (spirc != SPI_OK_SELECT) + elog(ERROR, "failed to get pg_rewrite tuple for view %u", viewoid); + if (SPI_processed != 1) + { + /* + * There is no tuple data available here, just keep the output buffer + * empty. + */ + } + else + { + /* + * Get the rule's definition and put it into executor's memory + */ + ruletup = SPI_tuptable->vals[0]; + rulettc = SPI_tuptable->tupdesc; + make_viewdef(&buf, ruletup, rulettc, prettyFlags, wrapColumn); + } + + /* + * Disconnect from SPI manager + */ + if (SPI_finish() != SPI_OK_FINISH) + elog(ERROR, "SPI_finish failed"); + + if (buf.len == 0) + return NULL; + + return buf.data; +} + +/* ---------- + * pg_get_triggerdef - Get the definition of a trigger + * ---------- + */ +Datum +pg_get_triggerdef(PG_FUNCTION_ARGS) +{ + Oid trigid = PG_GETARG_OID(0); + char *res; + + res = pg_get_triggerdef_worker(trigid, false); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +Datum +pg_get_triggerdef_ext(PG_FUNCTION_ARGS) +{ + Oid trigid = PG_GETARG_OID(0); + bool pretty = PG_GETARG_BOOL(1); + char *res; + + res = pg_get_triggerdef_worker(trigid, pretty); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +static char * +pg_get_triggerdef_worker(Oid trigid, bool pretty) +{ + HeapTuple ht_trig; + Form_pg_trigger trigrec; + StringInfoData buf; + Relation tgrel; + ScanKeyData skey[1]; + SysScanDesc tgscan; + int findx = 0; + char *tgname; + char *tgoldtable; + char *tgnewtable; + Datum value; + bool isnull; + + /* + * Fetch the pg_trigger tuple by the Oid of the trigger + */ + tgrel = table_open(TriggerRelationId, AccessShareLock); + + ScanKeyInit(&skey[0], + Anum_pg_trigger_oid, + BTEqualStrategyNumber, F_OIDEQ, + ObjectIdGetDatum(trigid)); + + tgscan = systable_beginscan(tgrel, TriggerOidIndexId, true, + NULL, 1, skey); + + ht_trig = systable_getnext(tgscan); + + if (!HeapTupleIsValid(ht_trig)) + { + systable_endscan(tgscan); + table_close(tgrel, AccessShareLock); + return NULL; + } + + trigrec = (Form_pg_trigger) GETSTRUCT(ht_trig); + + /* + * Start the trigger definition. Note that the trigger's name should never + * be schema-qualified, but the trigger rel's name may be. + */ + initStringInfo(&buf); + + tgname = NameStr(trigrec->tgname); + appendStringInfo(&buf, "CREATE %sTRIGGER %s ", + OidIsValid(trigrec->tgconstraint) ? "CONSTRAINT " : "", + quote_identifier(tgname)); + + if (TRIGGER_FOR_BEFORE(trigrec->tgtype)) + appendStringInfoString(&buf, "BEFORE"); + else if (TRIGGER_FOR_AFTER(trigrec->tgtype)) + appendStringInfoString(&buf, "AFTER"); + else if (TRIGGER_FOR_INSTEAD(trigrec->tgtype)) + appendStringInfoString(&buf, "INSTEAD OF"); + else + elog(ERROR, "unexpected tgtype value: %d", trigrec->tgtype); + + if (TRIGGER_FOR_INSERT(trigrec->tgtype)) + { + appendStringInfoString(&buf, " INSERT"); + findx++; + } + if (TRIGGER_FOR_DELETE(trigrec->tgtype)) + { + if (findx > 0) + appendStringInfoString(&buf, " OR DELETE"); + else + appendStringInfoString(&buf, " DELETE"); + findx++; + } + if (TRIGGER_FOR_UPDATE(trigrec->tgtype)) + { + if (findx > 0) + appendStringInfoString(&buf, " OR UPDATE"); + else + appendStringInfoString(&buf, " UPDATE"); + findx++; + /* tgattr is first var-width field, so OK to access directly */ + if (trigrec->tgattr.dim1 > 0) + { + int i; + + appendStringInfoString(&buf, " OF "); + for (i = 0; i < trigrec->tgattr.dim1; i++) + { + char *attname; + + if (i > 0) + appendStringInfoString(&buf, ", "); + attname = get_attname(trigrec->tgrelid, + trigrec->tgattr.values[i], false); + appendStringInfoString(&buf, quote_identifier(attname)); + } + } + } + if (TRIGGER_FOR_TRUNCATE(trigrec->tgtype)) + { + if (findx > 0) + appendStringInfoString(&buf, " OR TRUNCATE"); + else + appendStringInfoString(&buf, " TRUNCATE"); + findx++; + } + + /* + * In non-pretty mode, always schema-qualify the target table name for + * safety. In pretty mode, schema-qualify only if not visible. + */ + appendStringInfo(&buf, " ON %s ", + pretty ? + generate_relation_name(trigrec->tgrelid, NIL) : + generate_qualified_relation_name(trigrec->tgrelid)); + + if (OidIsValid(trigrec->tgconstraint)) + { + if (OidIsValid(trigrec->tgconstrrelid)) + appendStringInfo(&buf, "FROM %s ", + generate_relation_name(trigrec->tgconstrrelid, NIL)); + if (!trigrec->tgdeferrable) + appendStringInfoString(&buf, "NOT "); + appendStringInfoString(&buf, "DEFERRABLE INITIALLY "); + if (trigrec->tginitdeferred) + appendStringInfoString(&buf, "DEFERRED "); + else + appendStringInfoString(&buf, "IMMEDIATE "); + } + + value = fastgetattr(ht_trig, Anum_pg_trigger_tgoldtable, + tgrel->rd_att, &isnull); + if (!isnull) + tgoldtable = NameStr(*DatumGetName(value)); + else + tgoldtable = NULL; + value = fastgetattr(ht_trig, Anum_pg_trigger_tgnewtable, + tgrel->rd_att, &isnull); + if (!isnull) + tgnewtable = NameStr(*DatumGetName(value)); + else + tgnewtable = NULL; + if (tgoldtable != NULL || tgnewtable != NULL) + { + appendStringInfoString(&buf, "REFERENCING "); + if (tgoldtable != NULL) + appendStringInfo(&buf, "OLD TABLE AS %s ", + quote_identifier(tgoldtable)); + if (tgnewtable != NULL) + appendStringInfo(&buf, "NEW TABLE AS %s ", + quote_identifier(tgnewtable)); + } + + if (TRIGGER_FOR_ROW(trigrec->tgtype)) + appendStringInfoString(&buf, "FOR EACH ROW "); + else + appendStringInfoString(&buf, "FOR EACH STATEMENT "); + + /* If the trigger has a WHEN qualification, add that */ + value = fastgetattr(ht_trig, Anum_pg_trigger_tgqual, + tgrel->rd_att, &isnull); + if (!isnull) + { + Node *qual; + char relkind; + deparse_context context; + deparse_namespace dpns; + RangeTblEntry *oldrte; + RangeTblEntry *newrte; + + appendStringInfoString(&buf, "WHEN ("); + + qual = stringToNode(TextDatumGetCString(value)); + + relkind = get_rel_relkind(trigrec->tgrelid); + + /* Build minimal OLD and NEW RTEs for the rel */ + oldrte = makeNode(RangeTblEntry); + oldrte->rtekind = RTE_RELATION; + oldrte->relid = trigrec->tgrelid; + oldrte->relkind = relkind; + oldrte->rellockmode = AccessShareLock; + oldrte->alias = makeAlias("old", NIL); + oldrte->eref = oldrte->alias; + oldrte->lateral = false; + oldrte->inh = false; + oldrte->inFromCl = true; + + newrte = makeNode(RangeTblEntry); + newrte->rtekind = RTE_RELATION; + newrte->relid = trigrec->tgrelid; + newrte->relkind = relkind; + newrte->rellockmode = AccessShareLock; + newrte->alias = makeAlias("new", NIL); + newrte->eref = newrte->alias; + newrte->lateral = false; + newrte->inh = false; + newrte->inFromCl = true; + + /* Build two-element rtable */ + memset(&dpns, 0, sizeof(dpns)); + dpns.rtable = list_make2(oldrte, newrte); + dpns.subplans = NIL; + dpns.ctes = NIL; + dpns.appendrels = NULL; + set_rtable_names(&dpns, NIL, NULL); + set_simple_column_names(&dpns); + + /* Set up context with one-deep namespace stack */ + context.buf = &buf; + context.namespaces = list_make1(&dpns); + context.windowClause = NIL; + context.windowTList = NIL; + context.varprefix = true; + context.prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + context.wrapColumn = WRAP_COLUMN_DEFAULT; + context.indentLevel = PRETTYINDENT_STD; + context.special_exprkind = EXPR_KIND_NONE; + context.appendparents = NULL; + + get_rule_expr(qual, &context, false); + + appendStringInfoString(&buf, ") "); + } + + appendStringInfo(&buf, "EXECUTE FUNCTION %s(", + generate_function_name(trigrec->tgfoid, 0, + NIL, NULL, + false, NULL, EXPR_KIND_NONE)); + + if (trigrec->tgnargs > 0) + { + char *p; + int i; + + value = fastgetattr(ht_trig, Anum_pg_trigger_tgargs, + tgrel->rd_att, &isnull); + if (isnull) + elog(ERROR, "tgargs is null for trigger %u", trigid); + p = (char *) VARDATA_ANY(DatumGetByteaPP(value)); + for (i = 0; i < trigrec->tgnargs; i++) + { + if (i > 0) + appendStringInfoString(&buf, ", "); + simple_quote_literal(&buf, p); + /* advance p to next string embedded in tgargs */ + while (*p) + p++; + p++; + } + } + + /* We deliberately do not put semi-colon at end */ + appendStringInfoChar(&buf, ')'); + + /* Clean up */ + systable_endscan(tgscan); + + table_close(tgrel, AccessShareLock); + + return buf.data; +} + +/* ---------- + * pg_get_indexdef - Get the definition of an index + * + * In the extended version, there is a colno argument as well as pretty bool. + * if colno == 0, we want a complete index definition. + * if colno > 0, we only want the Nth index key's variable or expression. + * + * Note that the SQL-function versions of this omit any info about the + * index tablespace; this is intentional because pg_dump wants it that way. + * However pg_get_indexdef_string() includes the index tablespace. + * ---------- + */ +Datum +pg_get_indexdef(PG_FUNCTION_ARGS) +{ + Oid indexrelid = PG_GETARG_OID(0); + int prettyFlags; + char *res; + + prettyFlags = PRETTYFLAG_INDENT; + + res = pg_get_indexdef_worker(indexrelid, 0, NULL, + false, false, + false, false, + prettyFlags, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +Datum +pg_get_indexdef_ext(PG_FUNCTION_ARGS) +{ + Oid indexrelid = PG_GETARG_OID(0); + int32 colno = PG_GETARG_INT32(1); + bool pretty = PG_GETARG_BOOL(2); + int prettyFlags; + char *res; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + res = pg_get_indexdef_worker(indexrelid, colno, NULL, + colno != 0, false, + false, false, + prettyFlags, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* + * Internal version for use by ALTER TABLE. + * Includes a tablespace clause in the result. + * Returns a palloc'd C string; no pretty-printing. + */ +char * +pg_get_indexdef_string(Oid indexrelid) +{ + return pg_get_indexdef_worker(indexrelid, 0, NULL, + false, false, + true, true, + 0, false); +} + +/* Internal version that just reports the key-column definitions */ +char * +pg_get_indexdef_columns(Oid indexrelid, bool pretty) +{ + int prettyFlags; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + return pg_get_indexdef_worker(indexrelid, 0, NULL, + true, true, + false, false, + prettyFlags, false); +} + +/* + * Internal workhorse to decompile an index definition. + * + * This is now used for exclusion constraints as well: if excludeOps is not + * NULL then it points to an array of exclusion operator OIDs. + */ +static char * +pg_get_indexdef_worker(Oid indexrelid, int colno, + const Oid *excludeOps, + bool attrsOnly, bool keysOnly, + bool showTblSpc, bool inherits, + int prettyFlags, bool missing_ok) +{ + /* might want a separate isConstraint parameter later */ + bool isConstraint = (excludeOps != NULL); + HeapTuple ht_idx; + HeapTuple ht_idxrel; + HeapTuple ht_am; + Form_pg_index idxrec; + Form_pg_class idxrelrec; + Form_pg_am amrec; + IndexAmRoutine *amroutine; + List *indexprs; + ListCell *indexpr_item; + List *context; + Oid indrelid; + int keyno; + Datum indcollDatum; + Datum indclassDatum; + Datum indoptionDatum; + bool isnull; + oidvector *indcollation; + oidvector *indclass; + int2vector *indoption; + StringInfoData buf; + char *str; + char *sep; + + /* + * Fetch the pg_index tuple by the Oid of the index + */ + ht_idx = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexrelid)); + if (!HeapTupleIsValid(ht_idx)) + { + if (missing_ok) + return NULL; + elog(ERROR, "cache lookup failed for index %u", indexrelid); + } + idxrec = (Form_pg_index) GETSTRUCT(ht_idx); + + indrelid = idxrec->indrelid; + Assert(indexrelid == idxrec->indexrelid); + + /* Must get indcollation, indclass, and indoption the hard way */ + indcollDatum = SysCacheGetAttr(INDEXRELID, ht_idx, + Anum_pg_index_indcollation, &isnull); + Assert(!isnull); + indcollation = (oidvector *) DatumGetPointer(indcollDatum); + + indclassDatum = SysCacheGetAttr(INDEXRELID, ht_idx, + Anum_pg_index_indclass, &isnull); + Assert(!isnull); + indclass = (oidvector *) DatumGetPointer(indclassDatum); + + indoptionDatum = SysCacheGetAttr(INDEXRELID, ht_idx, + Anum_pg_index_indoption, &isnull); + Assert(!isnull); + indoption = (int2vector *) DatumGetPointer(indoptionDatum); + + /* + * Fetch the pg_class tuple of the index relation + */ + ht_idxrel = SearchSysCache1(RELOID, ObjectIdGetDatum(indexrelid)); + if (!HeapTupleIsValid(ht_idxrel)) + elog(ERROR, "cache lookup failed for relation %u", indexrelid); + idxrelrec = (Form_pg_class) GETSTRUCT(ht_idxrel); + + /* + * Fetch the pg_am tuple of the index' access method + */ + ht_am = SearchSysCache1(AMOID, ObjectIdGetDatum(idxrelrec->relam)); + if (!HeapTupleIsValid(ht_am)) + elog(ERROR, "cache lookup failed for access method %u", + idxrelrec->relam); + amrec = (Form_pg_am) GETSTRUCT(ht_am); + + /* Fetch the index AM's API struct */ + amroutine = GetIndexAmRoutine(amrec->amhandler); + + /* + * Get the index expressions, if any. (NOTE: we do not use the relcache + * versions of the expressions and predicate, because we want to display + * non-const-folded expressions.) + */ + if (!heap_attisnull(ht_idx, Anum_pg_index_indexprs, NULL)) + { + Datum exprsDatum; + bool isnull; + char *exprsString; + + exprsDatum = SysCacheGetAttr(INDEXRELID, ht_idx, + Anum_pg_index_indexprs, &isnull); + Assert(!isnull); + exprsString = TextDatumGetCString(exprsDatum); + indexprs = (List *) stringToNode(exprsString); + pfree(exprsString); + } + else + indexprs = NIL; + + indexpr_item = list_head(indexprs); + + context = deparse_context_for(get_relation_name(indrelid), indrelid); + + /* + * Start the index definition. Note that the index's name should never be + * schema-qualified, but the indexed rel's name may be. + */ + initStringInfo(&buf); + + if (!attrsOnly) + { + if (!isConstraint) + appendStringInfo(&buf, "CREATE %sINDEX %s ON %s%s USING %s (", + idxrec->indisunique ? "UNIQUE " : "", + quote_identifier(NameStr(idxrelrec->relname)), + idxrelrec->relkind == RELKIND_PARTITIONED_INDEX + && !inherits ? "ONLY " : "", + (prettyFlags & PRETTYFLAG_SCHEMA) ? + generate_relation_name(indrelid, NIL) : + generate_qualified_relation_name(indrelid), + quote_identifier(NameStr(amrec->amname))); + else /* currently, must be EXCLUDE constraint */ + appendStringInfo(&buf, "EXCLUDE USING %s (", + quote_identifier(NameStr(amrec->amname))); + } + + /* + * Report the indexed attributes + */ + sep = ""; + for (keyno = 0; keyno < idxrec->indnatts; keyno++) + { + AttrNumber attnum = idxrec->indkey.values[keyno]; + Oid keycoltype; + Oid keycolcollation; + + /* + * Ignore non-key attributes if told to. + */ + if (keysOnly && keyno >= idxrec->indnkeyatts) + break; + + /* Otherwise, print INCLUDE to divide key and non-key attrs. */ + if (!colno && keyno == idxrec->indnkeyatts) + { + appendStringInfoString(&buf, ") INCLUDE ("); + sep = ""; + } + + if (!colno) + appendStringInfoString(&buf, sep); + sep = ", "; + + if (attnum != 0) + { + /* Simple index column */ + char *attname; + int32 keycoltypmod; + + attname = get_attname(indrelid, attnum, false); + if (!colno || colno == keyno + 1) + appendStringInfoString(&buf, quote_identifier(attname)); + get_atttypetypmodcoll(indrelid, attnum, + &keycoltype, &keycoltypmod, + &keycolcollation); + } + else + { + /* expressional index */ + Node *indexkey; + + if (indexpr_item == NULL) + elog(ERROR, "too few entries in indexprs list"); + indexkey = (Node *) lfirst(indexpr_item); + indexpr_item = lnext(indexprs, indexpr_item); + /* Deparse */ + str = deparse_expression_pretty(indexkey, context, false, false, + prettyFlags, 0); + if (!colno || colno == keyno + 1) + { + /* Need parens if it's not a bare function call */ + if (looks_like_function(indexkey)) + appendStringInfoString(&buf, str); + else + appendStringInfo(&buf, "(%s)", str); + } + keycoltype = exprType(indexkey); + keycolcollation = exprCollation(indexkey); + } + + /* Print additional decoration for (selected) key columns */ + if (!attrsOnly && keyno < idxrec->indnkeyatts && + (!colno || colno == keyno + 1)) + { + int16 opt = indoption->values[keyno]; + Oid indcoll = indcollation->values[keyno]; + Datum attoptions = get_attoptions(indexrelid, keyno + 1); + bool has_options = attoptions != (Datum) 0; + + /* Add collation, if not default for column */ + if (OidIsValid(indcoll) && indcoll != keycolcollation) + appendStringInfo(&buf, " COLLATE %s", + generate_collation_name((indcoll))); + + /* Add the operator class name, if not default */ + get_opclass_name(indclass->values[keyno], + has_options ? InvalidOid : keycoltype, &buf); + + if (has_options) + { + appendStringInfoString(&buf, " ("); + get_reloptions(&buf, attoptions); + appendStringInfoChar(&buf, ')'); + } + + /* Add options if relevant */ + if (amroutine->amcanorder) + { + /* if it supports sort ordering, report DESC and NULLS opts */ + if (opt & INDOPTION_DESC) + { + appendStringInfoString(&buf, " DESC"); + /* NULLS FIRST is the default in this case */ + if (!(opt & INDOPTION_NULLS_FIRST)) + appendStringInfoString(&buf, " NULLS LAST"); + } + else + { + if (opt & INDOPTION_NULLS_FIRST) + appendStringInfoString(&buf, " NULLS FIRST"); + } + } + + /* Add the exclusion operator if relevant */ + if (excludeOps != NULL) + appendStringInfo(&buf, " WITH %s", + generate_operator_name(excludeOps[keyno], + keycoltype, + keycoltype)); + } + } + + if (!attrsOnly) + { + appendStringInfoChar(&buf, ')'); + + /* + * If it has options, append "WITH (options)" + */ + str = flatten_reloptions(indexrelid); + if (str) + { + appendStringInfo(&buf, " WITH (%s)", str); + pfree(str); + } + + /* + * Print tablespace, but only if requested + */ + if (showTblSpc) + { + Oid tblspc; + + tblspc = get_rel_tablespace(indexrelid); + if (OidIsValid(tblspc)) + { + if (isConstraint) + appendStringInfoString(&buf, " USING INDEX"); + appendStringInfo(&buf, " TABLESPACE %s", + quote_identifier(get_tablespace_name(tblspc))); + } + } + + /* + * If it's a partial index, decompile and append the predicate + */ + if (!heap_attisnull(ht_idx, Anum_pg_index_indpred, NULL)) + { + Node *node; + Datum predDatum; + bool isnull; + char *predString; + + /* Convert text string to node tree */ + predDatum = SysCacheGetAttr(INDEXRELID, ht_idx, + Anum_pg_index_indpred, &isnull); + Assert(!isnull); + predString = TextDatumGetCString(predDatum); + node = (Node *) stringToNode(predString); + pfree(predString); + + /* Deparse */ + str = deparse_expression_pretty(node, context, false, false, + prettyFlags, 0); + if (isConstraint) + appendStringInfo(&buf, " WHERE (%s)", str); + else + appendStringInfo(&buf, " WHERE %s", str); + } + } + + /* Clean up */ + ReleaseSysCache(ht_idx); + ReleaseSysCache(ht_idxrel); + ReleaseSysCache(ht_am); + + return buf.data; +} + +/* + * pg_get_statisticsobjdef + * Get the definition of an extended statistics object + */ +Datum +pg_get_statisticsobjdef(PG_FUNCTION_ARGS) +{ + Oid statextid = PG_GETARG_OID(0); + char *res; + + res = pg_get_statisticsobj_worker(statextid, false, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* + * Internal version for use by ALTER TABLE. + * Includes a tablespace clause in the result. + * Returns a palloc'd C string; no pretty-printing. + */ +char * +pg_get_statisticsobjdef_string(Oid statextid) +{ + return pg_get_statisticsobj_worker(statextid, false, false); +} + +/* + * pg_get_statisticsobjdef_columns + * Get columns and expressions for an extended statistics object + */ +Datum +pg_get_statisticsobjdef_columns(PG_FUNCTION_ARGS) +{ + Oid statextid = PG_GETARG_OID(0); + char *res; + + res = pg_get_statisticsobj_worker(statextid, true, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* + * Internal workhorse to decompile an extended statistics object. + */ +static char * +pg_get_statisticsobj_worker(Oid statextid, bool columns_only, bool missing_ok) +{ + Form_pg_statistic_ext statextrec; + HeapTuple statexttup; + StringInfoData buf; + int colno; + char *nsp; + ArrayType *arr; + char *enabled; + Datum datum; + bool isnull; + bool ndistinct_enabled; + bool dependencies_enabled; + bool mcv_enabled; + int i; + List *context; + ListCell *lc; + List *exprs = NIL; + bool has_exprs; + int ncolumns; + + statexttup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(statextid)); + + if (!HeapTupleIsValid(statexttup)) + { + if (missing_ok) + return NULL; + elog(ERROR, "cache lookup failed for statistics object %u", statextid); + } + + /* has the statistics expressions? */ + has_exprs = !heap_attisnull(statexttup, Anum_pg_statistic_ext_stxexprs, NULL); + + statextrec = (Form_pg_statistic_ext) GETSTRUCT(statexttup); + + /* + * Get the statistics expressions, if any. (NOTE: we do not use the + * relcache versions of the expressions, because we want to display + * non-const-folded expressions.) + */ + if (has_exprs) + { + Datum exprsDatum; + bool isnull; + char *exprsString; + + exprsDatum = SysCacheGetAttr(STATEXTOID, statexttup, + Anum_pg_statistic_ext_stxexprs, &isnull); + Assert(!isnull); + exprsString = TextDatumGetCString(exprsDatum); + exprs = (List *) stringToNode(exprsString); + pfree(exprsString); + } + else + exprs = NIL; + + /* count the number of columns (attributes and expressions) */ + ncolumns = statextrec->stxkeys.dim1 + list_length(exprs); + + initStringInfo(&buf); + + if (!columns_only) + { + nsp = get_namespace_name(statextrec->stxnamespace); + appendStringInfo(&buf, "CREATE STATISTICS %s", + quote_qualified_identifier(nsp, + NameStr(statextrec->stxname))); + + /* + * Decode the stxkind column so that we know which stats types to + * print. + */ + datum = SysCacheGetAttr(STATEXTOID, statexttup, + Anum_pg_statistic_ext_stxkind, &isnull); + Assert(!isnull); + arr = DatumGetArrayTypeP(datum); + if (ARR_NDIM(arr) != 1 || + ARR_HASNULL(arr) || + ARR_ELEMTYPE(arr) != CHAROID) + elog(ERROR, "stxkind is not a 1-D char array"); + enabled = (char *) ARR_DATA_PTR(arr); + + ndistinct_enabled = false; + dependencies_enabled = false; + mcv_enabled = false; + + for (i = 0; i < ARR_DIMS(arr)[0]; i++) + { + if (enabled[i] == STATS_EXT_NDISTINCT) + ndistinct_enabled = true; + else if (enabled[i] == STATS_EXT_DEPENDENCIES) + dependencies_enabled = true; + else if (enabled[i] == STATS_EXT_MCV) + mcv_enabled = true; + + /* ignore STATS_EXT_EXPRESSIONS (it's built automatically) */ + } + + /* + * If any option is disabled, then we'll need to append the types + * clause to show which options are enabled. We omit the types clause + * on purpose when all options are enabled, so a pg_dump/pg_restore + * will create all statistics types on a newer postgres version, if + * the statistics had all options enabled on the original version. + * + * But if the statistics is defined on just a single column, it has to + * be an expression statistics. In that case we don't need to specify + * kinds. + */ + if ((!ndistinct_enabled || !dependencies_enabled || !mcv_enabled) && + (ncolumns > 1)) + { + bool gotone = false; + + appendStringInfoString(&buf, " ("); + + if (ndistinct_enabled) + { + appendStringInfoString(&buf, "ndistinct"); + gotone = true; + } + + if (dependencies_enabled) + { + appendStringInfo(&buf, "%sdependencies", gotone ? ", " : ""); + gotone = true; + } + + if (mcv_enabled) + appendStringInfo(&buf, "%smcv", gotone ? ", " : ""); + + appendStringInfoChar(&buf, ')'); + } + + appendStringInfoString(&buf, " ON "); + } + + /* decode simple column references */ + for (colno = 0; colno < statextrec->stxkeys.dim1; colno++) + { + AttrNumber attnum = statextrec->stxkeys.values[colno]; + char *attname; + + if (colno > 0) + appendStringInfoString(&buf, ", "); + + attname = get_attname(statextrec->stxrelid, attnum, false); + + appendStringInfoString(&buf, quote_identifier(attname)); + } + + context = deparse_context_for(get_relation_name(statextrec->stxrelid), + statextrec->stxrelid); + + foreach(lc, exprs) + { + Node *expr = (Node *) lfirst(lc); + char *str; + int prettyFlags = PRETTYFLAG_PAREN; + + str = deparse_expression_pretty(expr, context, false, false, + prettyFlags, 0); + + if (colno > 0) + appendStringInfoString(&buf, ", "); + + /* Need parens if it's not a bare function call */ + if (looks_like_function(expr)) + appendStringInfoString(&buf, str); + else + appendStringInfo(&buf, "(%s)", str); + + colno++; + } + + if (!columns_only) + appendStringInfo(&buf, " FROM %s", + generate_relation_name(statextrec->stxrelid, NIL)); + + ReleaseSysCache(statexttup); + + return buf.data; +} + +/* + * Generate text array of expressions for statistics object. + */ +Datum +pg_get_statisticsobjdef_expressions(PG_FUNCTION_ARGS) +{ + Oid statextid = PG_GETARG_OID(0); + Form_pg_statistic_ext statextrec; + HeapTuple statexttup; + Datum datum; + bool isnull; + List *context; + ListCell *lc; + List *exprs = NIL; + bool has_exprs; + char *tmp; + ArrayBuildState *astate = NULL; + + statexttup = SearchSysCache1(STATEXTOID, ObjectIdGetDatum(statextid)); + + if (!HeapTupleIsValid(statexttup)) + PG_RETURN_NULL(); + + /* Does the stats object have expressions? */ + has_exprs = !heap_attisnull(statexttup, Anum_pg_statistic_ext_stxexprs, NULL); + + /* no expressions? we're done */ + if (!has_exprs) + { + ReleaseSysCache(statexttup); + PG_RETURN_NULL(); + } + + statextrec = (Form_pg_statistic_ext) GETSTRUCT(statexttup); + + /* + * Get the statistics expressions, and deparse them into text values. + */ + datum = SysCacheGetAttr(STATEXTOID, statexttup, + Anum_pg_statistic_ext_stxexprs, &isnull); + + Assert(!isnull); + tmp = TextDatumGetCString(datum); + exprs = (List *) stringToNode(tmp); + pfree(tmp); + + context = deparse_context_for(get_relation_name(statextrec->stxrelid), + statextrec->stxrelid); + + foreach(lc, exprs) + { + Node *expr = (Node *) lfirst(lc); + char *str; + int prettyFlags = PRETTYFLAG_INDENT; + + str = deparse_expression_pretty(expr, context, false, false, + prettyFlags, 0); + + astate = accumArrayResult(astate, + PointerGetDatum(cstring_to_text(str)), + false, + TEXTOID, + CurrentMemoryContext); + } + + ReleaseSysCache(statexttup); + + PG_RETURN_DATUM(makeArrayResult(astate, CurrentMemoryContext)); +} + +/* + * pg_get_partkeydef + * + * Returns the partition key specification, ie, the following: + * + * PARTITION BY { RANGE | LIST | HASH } (column opt_collation opt_opclass [, ...]) + */ +Datum +pg_get_partkeydef(PG_FUNCTION_ARGS) +{ + Oid relid = PG_GETARG_OID(0); + char *res; + + res = pg_get_partkeydef_worker(relid, PRETTYFLAG_INDENT, false, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* Internal version that just reports the column definitions */ +char * +pg_get_partkeydef_columns(Oid relid, bool pretty) +{ + int prettyFlags; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + return pg_get_partkeydef_worker(relid, prettyFlags, true, false); +} + +/* + * Internal workhorse to decompile a partition key definition. + */ +static char * +pg_get_partkeydef_worker(Oid relid, int prettyFlags, + bool attrsOnly, bool missing_ok) +{ + Form_pg_partitioned_table form; + HeapTuple tuple; + oidvector *partclass; + oidvector *partcollation; + List *partexprs; + ListCell *partexpr_item; + List *context; + Datum datum; + bool isnull; + StringInfoData buf; + int keyno; + char *str; + char *sep; + + tuple = SearchSysCache1(PARTRELID, ObjectIdGetDatum(relid)); + if (!HeapTupleIsValid(tuple)) + { + if (missing_ok) + return NULL; + elog(ERROR, "cache lookup failed for partition key of %u", relid); + } + + form = (Form_pg_partitioned_table) GETSTRUCT(tuple); + + Assert(form->partrelid == relid); + + /* Must get partclass and partcollation the hard way */ + datum = SysCacheGetAttr(PARTRELID, tuple, + Anum_pg_partitioned_table_partclass, &isnull); + Assert(!isnull); + partclass = (oidvector *) DatumGetPointer(datum); + + datum = SysCacheGetAttr(PARTRELID, tuple, + Anum_pg_partitioned_table_partcollation, &isnull); + Assert(!isnull); + partcollation = (oidvector *) DatumGetPointer(datum); + + + /* + * Get the expressions, if any. (NOTE: we do not use the relcache + * versions of the expressions, because we want to display + * non-const-folded expressions.) + */ + if (!heap_attisnull(tuple, Anum_pg_partitioned_table_partexprs, NULL)) + { + Datum exprsDatum; + bool isnull; + char *exprsString; + + exprsDatum = SysCacheGetAttr(PARTRELID, tuple, + Anum_pg_partitioned_table_partexprs, &isnull); + Assert(!isnull); + exprsString = TextDatumGetCString(exprsDatum); + partexprs = (List *) stringToNode(exprsString); + + if (!IsA(partexprs, List)) + elog(ERROR, "unexpected node type found in partexprs: %d", + (int) nodeTag(partexprs)); + + pfree(exprsString); + } + else + partexprs = NIL; + + partexpr_item = list_head(partexprs); + context = deparse_context_for(get_relation_name(relid), relid); + + initStringInfo(&buf); + + switch (form->partstrat) + { + case PARTITION_STRATEGY_HASH: + if (!attrsOnly) + appendStringInfoString(&buf, "HASH"); + break; + case PARTITION_STRATEGY_LIST: + if (!attrsOnly) + appendStringInfoString(&buf, "LIST"); + break; + case PARTITION_STRATEGY_RANGE: + if (!attrsOnly) + appendStringInfoString(&buf, "RANGE"); + break; + default: + elog(ERROR, "unexpected partition strategy: %d", + (int) form->partstrat); + } + + if (!attrsOnly) + appendStringInfoString(&buf, " ("); + sep = ""; + for (keyno = 0; keyno < form->partnatts; keyno++) + { + AttrNumber attnum = form->partattrs.values[keyno]; + Oid keycoltype; + Oid keycolcollation; + Oid partcoll; + + appendStringInfoString(&buf, sep); + sep = ", "; + if (attnum != 0) + { + /* Simple attribute reference */ + char *attname; + int32 keycoltypmod; + + attname = get_attname(relid, attnum, false); + appendStringInfoString(&buf, quote_identifier(attname)); + get_atttypetypmodcoll(relid, attnum, + &keycoltype, &keycoltypmod, + &keycolcollation); + } + else + { + /* Expression */ + Node *partkey; + + if (partexpr_item == NULL) + elog(ERROR, "too few entries in partexprs list"); + partkey = (Node *) lfirst(partexpr_item); + partexpr_item = lnext(partexprs, partexpr_item); + + /* Deparse */ + str = deparse_expression_pretty(partkey, context, false, false, + prettyFlags, 0); + /* Need parens if it's not a bare function call */ + if (looks_like_function(partkey)) + appendStringInfoString(&buf, str); + else + appendStringInfo(&buf, "(%s)", str); + + keycoltype = exprType(partkey); + keycolcollation = exprCollation(partkey); + } + + /* Add collation, if not default for column */ + partcoll = partcollation->values[keyno]; + if (!attrsOnly && OidIsValid(partcoll) && partcoll != keycolcollation) + appendStringInfo(&buf, " COLLATE %s", + generate_collation_name((partcoll))); + + /* Add the operator class name, if not default */ + if (!attrsOnly) + get_opclass_name(partclass->values[keyno], keycoltype, &buf); + } + + if (!attrsOnly) + appendStringInfoChar(&buf, ')'); + + /* Clean up */ + ReleaseSysCache(tuple); + + return buf.data; +} + +/* + * pg_get_partition_constraintdef + * + * Returns partition constraint expression as a string for the input relation + */ +Datum +pg_get_partition_constraintdef(PG_FUNCTION_ARGS) +{ + Oid relationId = PG_GETARG_OID(0); + Expr *constr_expr; + int prettyFlags; + List *context; + char *consrc; + + constr_expr = get_partition_qual_relid(relationId); + + /* Quick exit if no partition constraint */ + if (constr_expr == NULL) + PG_RETURN_NULL(); + + /* + * Deparse and return the constraint expression. + */ + prettyFlags = PRETTYFLAG_INDENT; + context = deparse_context_for(get_relation_name(relationId), relationId); + consrc = deparse_expression_pretty((Node *) constr_expr, context, false, + false, prettyFlags, 0); + + PG_RETURN_TEXT_P(string_to_text(consrc)); +} + +/* + * pg_get_partconstrdef_string + * + * Returns the partition constraint as a C-string for the input relation, with + * the given alias. No pretty-printing. + */ +char * +pg_get_partconstrdef_string(Oid partitionId, char *aliasname) +{ + Expr *constr_expr; + List *context; + + constr_expr = get_partition_qual_relid(partitionId); + context = deparse_context_for(aliasname, partitionId); + + return deparse_expression((Node *) constr_expr, context, true, false); +} + +/* + * pg_get_constraintdef + * + * Returns the definition for the constraint, ie, everything that needs to + * appear after "ALTER TABLE ... ADD CONSTRAINT <constraintname>". + */ +Datum +pg_get_constraintdef(PG_FUNCTION_ARGS) +{ + Oid constraintId = PG_GETARG_OID(0); + int prettyFlags; + char *res; + + prettyFlags = PRETTYFLAG_INDENT; + + res = pg_get_constraintdef_worker(constraintId, false, prettyFlags, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +Datum +pg_get_constraintdef_ext(PG_FUNCTION_ARGS) +{ + Oid constraintId = PG_GETARG_OID(0); + bool pretty = PG_GETARG_BOOL(1); + int prettyFlags; + char *res; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + res = pg_get_constraintdef_worker(constraintId, false, prettyFlags, true); + + if (res == NULL) + PG_RETURN_NULL(); + + PG_RETURN_TEXT_P(string_to_text(res)); +} + +/* + * Internal version that returns a full ALTER TABLE ... ADD CONSTRAINT command + */ +char * +pg_get_constraintdef_command(Oid constraintId) +{ + return pg_get_constraintdef_worker(constraintId, true, 0, false); +} + +/* + * As of 9.4, we now use an MVCC snapshot for this. + */ +static char * +pg_get_constraintdef_worker(Oid constraintId, bool fullCommand, + int prettyFlags, bool missing_ok) +{ + HeapTuple tup; + Form_pg_constraint conForm; + StringInfoData buf; + SysScanDesc scandesc; + ScanKeyData scankey[1]; + Snapshot snapshot = RegisterSnapshot(GetTransactionSnapshot()); + Relation relation = table_open(ConstraintRelationId, AccessShareLock); + + ScanKeyInit(&scankey[0], + Anum_pg_constraint_oid, + BTEqualStrategyNumber, F_OIDEQ, + ObjectIdGetDatum(constraintId)); + + scandesc = systable_beginscan(relation, + ConstraintOidIndexId, + true, + snapshot, + 1, + scankey); + + /* + * We later use the tuple with SysCacheGetAttr() as if we had obtained it + * via SearchSysCache, which works fine. + */ + tup = systable_getnext(scandesc); + + UnregisterSnapshot(snapshot); + + if (!HeapTupleIsValid(tup)) + { + if (missing_ok) + { + systable_endscan(scandesc); + table_close(relation, AccessShareLock); + return NULL; + } + elog(ERROR, "could not find tuple for constraint %u", constraintId); + } + + conForm = (Form_pg_constraint) GETSTRUCT(tup); + + initStringInfo(&buf); + + if (fullCommand) + { + if (OidIsValid(conForm->conrelid)) + { + /* + * Currently, callers want ALTER TABLE (without ONLY) for CHECK + * constraints, and other types of constraints don't inherit + * anyway so it doesn't matter whether we say ONLY or not. Someday + * we might need to let callers specify whether to put ONLY in the + * command. + */ + appendStringInfo(&buf, "ALTER TABLE %s ADD CONSTRAINT %s ", + generate_qualified_relation_name(conForm->conrelid), + quote_identifier(NameStr(conForm->conname))); + } + else + { + /* Must be a domain constraint */ + Assert(OidIsValid(conForm->contypid)); + appendStringInfo(&buf, "ALTER DOMAIN %s ADD CONSTRAINT %s ", + generate_qualified_type_name(conForm->contypid), + quote_identifier(NameStr(conForm->conname))); + } + } + + switch (conForm->contype) + { + case CONSTRAINT_FOREIGN: + { + Datum val; + bool isnull; + const char *string; + + /* Start off the constraint definition */ + appendStringInfoString(&buf, "FOREIGN KEY ("); + + /* Fetch and build referencing-column list */ + val = SysCacheGetAttr(CONSTROID, tup, + Anum_pg_constraint_conkey, &isnull); + if (isnull) + elog(ERROR, "null conkey for constraint %u", + constraintId); + + decompile_column_index_array(val, conForm->conrelid, &buf); + + /* add foreign relation name */ + appendStringInfo(&buf, ") REFERENCES %s(", + generate_relation_name(conForm->confrelid, + NIL)); + + /* Fetch and build referenced-column list */ + val = SysCacheGetAttr(CONSTROID, tup, + Anum_pg_constraint_confkey, &isnull); + if (isnull) + elog(ERROR, "null confkey for constraint %u", + constraintId); + + decompile_column_index_array(val, conForm->confrelid, &buf); + + appendStringInfoChar(&buf, ')'); + + /* Add match type */ + switch (conForm->confmatchtype) + { + case FKCONSTR_MATCH_FULL: + string = " MATCH FULL"; + break; + case FKCONSTR_MATCH_PARTIAL: + string = " MATCH PARTIAL"; + break; + case FKCONSTR_MATCH_SIMPLE: + string = ""; + break; + default: + elog(ERROR, "unrecognized confmatchtype: %d", + conForm->confmatchtype); + string = ""; /* keep compiler quiet */ + break; + } + appendStringInfoString(&buf, string); + + /* Add ON UPDATE and ON DELETE clauses, if needed */ + switch (conForm->confupdtype) + { + case FKCONSTR_ACTION_NOACTION: + string = NULL; /* suppress default */ + break; + case FKCONSTR_ACTION_RESTRICT: + string = "RESTRICT"; + break; + case FKCONSTR_ACTION_CASCADE: + string = "CASCADE"; + break; + case FKCONSTR_ACTION_SETNULL: + string = "SET NULL"; + break; + case FKCONSTR_ACTION_SETDEFAULT: + string = "SET DEFAULT"; + break; + default: + elog(ERROR, "unrecognized confupdtype: %d", + conForm->confupdtype); + string = NULL; /* keep compiler quiet */ + break; + } + if (string) + appendStringInfo(&buf, " ON UPDATE %s", string); + + switch (conForm->confdeltype) + { + case FKCONSTR_ACTION_NOACTION: + string = NULL; /* suppress default */ + break; + case FKCONSTR_ACTION_RESTRICT: + string = "RESTRICT"; + break; + case FKCONSTR_ACTION_CASCADE: + string = "CASCADE"; + break; + case FKCONSTR_ACTION_SETNULL: + string = "SET NULL"; + break; + case FKCONSTR_ACTION_SETDEFAULT: + string = "SET DEFAULT"; + break; + default: + elog(ERROR, "unrecognized confdeltype: %d", + conForm->confdeltype); + string = NULL; /* keep compiler quiet */ + break; + } + if (string) + appendStringInfo(&buf, " ON DELETE %s", string); + + break; + } + case CONSTRAINT_PRIMARY: + case CONSTRAINT_UNIQUE: + { + Datum val; + bool isnull; + Oid indexId; + int keyatts; + HeapTuple indtup; + + /* Start off the constraint definition */ + if (conForm->contype == CONSTRAINT_PRIMARY) + appendStringInfoString(&buf, "PRIMARY KEY ("); + else + appendStringInfoString(&buf, "UNIQUE ("); + + /* Fetch and build target column list */ + val = SysCacheGetAttr(CONSTROID, tup, + Anum_pg_constraint_conkey, &isnull); + if (isnull) + elog(ERROR, "null conkey for constraint %u", + constraintId); + + keyatts = decompile_column_index_array(val, conForm->conrelid, &buf); + + appendStringInfoChar(&buf, ')'); + + indexId = conForm->conindid; + + /* Build including column list (from pg_index.indkeys) */ + indtup = SearchSysCache1(INDEXRELID, ObjectIdGetDatum(indexId)); + if (!HeapTupleIsValid(indtup)) + elog(ERROR, "cache lookup failed for index %u", indexId); + val = SysCacheGetAttr(INDEXRELID, indtup, + Anum_pg_index_indnatts, &isnull); + if (isnull) + elog(ERROR, "null indnatts for index %u", indexId); + if (DatumGetInt32(val) > keyatts) + { + Datum cols; + Datum *keys; + int nKeys; + int j; + + appendStringInfoString(&buf, " INCLUDE ("); + + cols = SysCacheGetAttr(INDEXRELID, indtup, + Anum_pg_index_indkey, &isnull); + if (isnull) + elog(ERROR, "null indkey for index %u", indexId); + + deconstruct_array(DatumGetArrayTypeP(cols), + INT2OID, 2, true, TYPALIGN_SHORT, + &keys, NULL, &nKeys); + + for (j = keyatts; j < nKeys; j++) + { + char *colName; + + colName = get_attname(conForm->conrelid, + DatumGetInt16(keys[j]), false); + if (j > keyatts) + appendStringInfoString(&buf, ", "); + appendStringInfoString(&buf, quote_identifier(colName)); + } + + appendStringInfoChar(&buf, ')'); + } + ReleaseSysCache(indtup); + + /* XXX why do we only print these bits if fullCommand? */ + if (fullCommand && OidIsValid(indexId)) + { + char *options = flatten_reloptions(indexId); + Oid tblspc; + + if (options) + { + appendStringInfo(&buf, " WITH (%s)", options); + pfree(options); + } + + /* + * Print the tablespace, unless it's the database default. + * This is to help ALTER TABLE usage of this facility, + * which needs this behavior to recreate exact catalog + * state. + */ + tblspc = get_rel_tablespace(indexId); + if (OidIsValid(tblspc)) + appendStringInfo(&buf, " USING INDEX TABLESPACE %s", + quote_identifier(get_tablespace_name(tblspc))); + } + + break; + } + case CONSTRAINT_CHECK: + { + Datum val; + bool isnull; + char *conbin; + char *consrc; + Node *expr; + List *context; + + /* Fetch constraint expression in parsetree form */ + val = SysCacheGetAttr(CONSTROID, tup, + Anum_pg_constraint_conbin, &isnull); + if (isnull) + elog(ERROR, "null conbin for constraint %u", + constraintId); + + conbin = TextDatumGetCString(val); + expr = stringToNode(conbin); + + /* Set up deparsing context for Var nodes in constraint */ + if (conForm->conrelid != InvalidOid) + { + /* relation constraint */ + context = deparse_context_for(get_relation_name(conForm->conrelid), + conForm->conrelid); + } + else + { + /* domain constraint --- can't have Vars */ + context = NIL; + } + + consrc = deparse_expression_pretty(expr, context, false, false, + prettyFlags, 0); + + /* + * Now emit the constraint definition, adding NO INHERIT if + * necessary. + * + * There are cases where the constraint expression will be + * fully parenthesized and we don't need the outer parens ... + * but there are other cases where we do need 'em. Be + * conservative for now. + * + * Note that simply checking for leading '(' and trailing ')' + * would NOT be good enough, consider "(x > 0) AND (y > 0)". + */ + appendStringInfo(&buf, "CHECK (%s)%s", + consrc, + conForm->connoinherit ? " NO INHERIT" : ""); + break; + } + case CONSTRAINT_TRIGGER: + + /* + * There isn't an ALTER TABLE syntax for creating a user-defined + * constraint trigger, but it seems better to print something than + * throw an error; if we throw error then this function couldn't + * safely be applied to all rows of pg_constraint. + */ + appendStringInfoString(&buf, "TRIGGER"); + break; + case CONSTRAINT_EXCLUSION: + { + Oid indexOid = conForm->conindid; + Datum val; + bool isnull; + Datum *elems; + int nElems; + int i; + Oid *operators; + + /* Extract operator OIDs from the pg_constraint tuple */ + val = SysCacheGetAttr(CONSTROID, tup, + Anum_pg_constraint_conexclop, + &isnull); + if (isnull) + elog(ERROR, "null conexclop for constraint %u", + constraintId); + + deconstruct_array(DatumGetArrayTypeP(val), + OIDOID, sizeof(Oid), true, TYPALIGN_INT, + &elems, NULL, &nElems); + + operators = (Oid *) palloc(nElems * sizeof(Oid)); + for (i = 0; i < nElems; i++) + operators[i] = DatumGetObjectId(elems[i]); + + /* pg_get_indexdef_worker does the rest */ + /* suppress tablespace because pg_dump wants it that way */ + appendStringInfoString(&buf, + pg_get_indexdef_worker(indexOid, + 0, + operators, + false, + false, + false, + false, + prettyFlags, + false)); + break; + } + default: + elog(ERROR, "invalid constraint type \"%c\"", conForm->contype); + break; + } + + if (conForm->condeferrable) + appendStringInfoString(&buf, " DEFERRABLE"); + if (conForm->condeferred) + appendStringInfoString(&buf, " INITIALLY DEFERRED"); + if (!conForm->convalidated) + appendStringInfoString(&buf, " NOT VALID"); + + /* Cleanup */ + systable_endscan(scandesc); + table_close(relation, AccessShareLock); + + return buf.data; +} + + +/* + * Convert an int16[] Datum into a comma-separated list of column names + * for the indicated relation; append the list to buf. Returns the number + * of keys. + */ +static int +decompile_column_index_array(Datum column_index_array, Oid relId, + StringInfo buf) +{ + Datum *keys; + int nKeys; + int j; + + /* Extract data from array of int16 */ + deconstruct_array(DatumGetArrayTypeP(column_index_array), + INT2OID, 2, true, TYPALIGN_SHORT, + &keys, NULL, &nKeys); + + for (j = 0; j < nKeys; j++) + { + char *colName; + + colName = get_attname(relId, DatumGetInt16(keys[j]), false); + + if (j == 0) + appendStringInfoString(buf, quote_identifier(colName)); + else + appendStringInfo(buf, ", %s", quote_identifier(colName)); + } + + return nKeys; +} + + +/* ---------- + * pg_get_expr - Decompile an expression tree + * + * Input: an expression tree in nodeToString form, and a relation OID + * + * Output: reverse-listed expression + * + * Currently, the expression can only refer to a single relation, namely + * the one specified by the second parameter. This is sufficient for + * partial indexes, column default expressions, etc. We also support + * Var-free expressions, for which the OID can be InvalidOid. + * ---------- + */ +Datum +pg_get_expr(PG_FUNCTION_ARGS) +{ + text *expr = PG_GETARG_TEXT_PP(0); + Oid relid = PG_GETARG_OID(1); + int prettyFlags; + char *relname; + + prettyFlags = PRETTYFLAG_INDENT; + + if (OidIsValid(relid)) + { + /* Get the name for the relation */ + relname = get_rel_name(relid); + + /* + * If the OID isn't actually valid, don't throw an error, just return + * NULL. This is a bit questionable, but it's what we've done + * historically, and it can help avoid unwanted failures when + * examining catalog entries for just-deleted relations. + */ + if (relname == NULL) + PG_RETURN_NULL(); + } + else + relname = NULL; + + PG_RETURN_TEXT_P(pg_get_expr_worker(expr, relid, relname, prettyFlags)); +} + +Datum +pg_get_expr_ext(PG_FUNCTION_ARGS) +{ + text *expr = PG_GETARG_TEXT_PP(0); + Oid relid = PG_GETARG_OID(1); + bool pretty = PG_GETARG_BOOL(2); + int prettyFlags; + char *relname; + + prettyFlags = pretty ? (PRETTYFLAG_PAREN | PRETTYFLAG_INDENT | PRETTYFLAG_SCHEMA) : PRETTYFLAG_INDENT; + + if (OidIsValid(relid)) + { + /* Get the name for the relation */ + relname = get_rel_name(relid); + /* See notes above */ + if (relname == NULL) + PG_RETURN_NULL(); + } + else + relname = NULL; + + PG_RETURN_TEXT_P(pg_get_expr_worker(expr, relid, relname, prettyFlags)); +} + +static text * +pg_get_expr_worker(text *expr, Oid relid, const char *relname, int prettyFlags) +{ + Node *node; + List *context; + char *exprstr; + char *str; + + /* Convert input TEXT object to C string */ + exprstr = text_to_cstring(expr); + + /* Convert expression to node tree */ + node = (Node *) stringToNode(exprstr); + + pfree(exprstr); + + /* Prepare deparse context if needed */ + if (OidIsValid(relid)) + context = deparse_context_for(relname, relid); + else + context = NIL; + + /* Deparse */ + str = deparse_expression_pretty(node, context, false, false, + prettyFlags, 0); + + return string_to_text(str); +} + + +/* ---------- + * pg_get_userbyid - Get a user name by roleid and + * fallback to 'unknown (OID=n)' + * ---------- + */ +Datum +pg_get_userbyid(PG_FUNCTION_ARGS) +{ + Oid roleid = PG_GETARG_OID(0); + Name result; + HeapTuple roletup; + Form_pg_authid role_rec; + + /* + * Allocate space for the result + */ + result = (Name) palloc(NAMEDATALEN); + memset(NameStr(*result), 0, NAMEDATALEN); + + /* + * Get the pg_authid entry and print the result + */ + roletup = SearchSysCache1(AUTHOID, ObjectIdGetDatum(roleid)); + if (HeapTupleIsValid(roletup)) + { + role_rec = (Form_pg_authid) GETSTRUCT(roletup); + *result = role_rec->rolname; + ReleaseSysCache(roletup); + } + else + sprintf(NameStr(*result), "unknown (OID=%u)", roleid); + + PG_RETURN_NAME(result); +} + + +/* + * pg_get_serial_sequence + * Get the name of the sequence used by an identity or serial column, + * formatted suitably for passing to setval, nextval or currval. + * First parameter is not treated as double-quoted, second parameter + * is --- see documentation for reason. + */ +Datum +pg_get_serial_sequence(PG_FUNCTION_ARGS) +{ + text *tablename = PG_GETARG_TEXT_PP(0); + text *columnname = PG_GETARG_TEXT_PP(1); + RangeVar *tablerv; + Oid tableOid; + char *column; + AttrNumber attnum; + Oid sequenceId = InvalidOid; + Relation depRel; + ScanKeyData key[3]; + SysScanDesc scan; + HeapTuple tup; + + /* Look up table name. Can't lock it - we might not have privileges. */ + tablerv = makeRangeVarFromNameList(textToQualifiedNameList(tablename)); + tableOid = RangeVarGetRelid(tablerv, NoLock, false); + + /* Get the number of the column */ + column = text_to_cstring(columnname); + + attnum = get_attnum(tableOid, column); + if (attnum == InvalidAttrNumber) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_COLUMN), + errmsg("column \"%s\" of relation \"%s\" does not exist", + column, tablerv->relname))); + + /* Search the dependency table for the dependent sequence */ + depRel = table_open(DependRelationId, AccessShareLock); + + ScanKeyInit(&key[0], + Anum_pg_depend_refclassid, + BTEqualStrategyNumber, F_OIDEQ, + ObjectIdGetDatum(RelationRelationId)); + ScanKeyInit(&key[1], + Anum_pg_depend_refobjid, + BTEqualStrategyNumber, F_OIDEQ, + ObjectIdGetDatum(tableOid)); + ScanKeyInit(&key[2], + Anum_pg_depend_refobjsubid, + BTEqualStrategyNumber, F_INT4EQ, + Int32GetDatum(attnum)); + + scan = systable_beginscan(depRel, DependReferenceIndexId, true, + NULL, 3, key); + + while (HeapTupleIsValid(tup = systable_getnext(scan))) + { + Form_pg_depend deprec = (Form_pg_depend) GETSTRUCT(tup); + + /* + * Look for an auto dependency (serial column) or internal dependency + * (identity column) of a sequence on a column. (We need the relkind + * test because indexes can also have auto dependencies on columns.) + */ + if (deprec->classid == RelationRelationId && + deprec->objsubid == 0 && + (deprec->deptype == DEPENDENCY_AUTO || + deprec->deptype == DEPENDENCY_INTERNAL) && + get_rel_relkind(deprec->objid) == RELKIND_SEQUENCE) + { + sequenceId = deprec->objid; + break; + } + } + + systable_endscan(scan); + table_close(depRel, AccessShareLock); + + if (OidIsValid(sequenceId)) + { + char *result; + + result = generate_qualified_relation_name(sequenceId); + + PG_RETURN_TEXT_P(string_to_text(result)); + } + + PG_RETURN_NULL(); +} + + +/* + * pg_get_functiondef + * Returns the complete "CREATE OR REPLACE FUNCTION ..." statement for + * the specified function. + * + * Note: if you change the output format of this function, be careful not + * to break psql's rules (in \ef and \sf) for identifying the start of the + * function body. To wit: the function body starts on a line that begins + * with "AS ", and no preceding line will look like that. + */ +Datum +pg_get_functiondef(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + StringInfoData buf; + StringInfoData dq; + HeapTuple proctup; + Form_pg_proc proc; + bool isfunction; + Datum tmp; + bool isnull; + const char *prosrc; + const char *name; + const char *nsp; + float4 procost; + int oldlen; + + initStringInfo(&buf); + + /* Look up the function */ + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + proc = (Form_pg_proc) GETSTRUCT(proctup); + name = NameStr(proc->proname); + + if (proc->prokind == PROKIND_AGGREGATE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an aggregate function", name))); + + isfunction = (proc->prokind != PROKIND_PROCEDURE); + + /* + * We always qualify the function name, to ensure the right function gets + * replaced. + */ + nsp = get_namespace_name(proc->pronamespace); + appendStringInfo(&buf, "CREATE OR REPLACE %s %s(", + isfunction ? "FUNCTION" : "PROCEDURE", + quote_qualified_identifier(nsp, name)); + (void) print_function_arguments(&buf, proctup, false, true); + appendStringInfoString(&buf, ")\n"); + if (isfunction) + { + appendStringInfoString(&buf, " RETURNS "); + print_function_rettype(&buf, proctup); + appendStringInfoChar(&buf, '\n'); + } + + print_function_trftypes(&buf, proctup); + + appendStringInfo(&buf, " LANGUAGE %s\n", + quote_identifier(get_language_name(proc->prolang, false))); + + /* Emit some miscellaneous options on one line */ + oldlen = buf.len; + + if (proc->prokind == PROKIND_WINDOW) + appendStringInfoString(&buf, " WINDOW"); + switch (proc->provolatile) + { + case PROVOLATILE_IMMUTABLE: + appendStringInfoString(&buf, " IMMUTABLE"); + break; + case PROVOLATILE_STABLE: + appendStringInfoString(&buf, " STABLE"); + break; + case PROVOLATILE_VOLATILE: + break; + } + + switch (proc->proparallel) + { + case PROPARALLEL_SAFE: + appendStringInfoString(&buf, " PARALLEL SAFE"); + break; + case PROPARALLEL_RESTRICTED: + appendStringInfoString(&buf, " PARALLEL RESTRICTED"); + break; + case PROPARALLEL_UNSAFE: + break; + } + + if (proc->proisstrict) + appendStringInfoString(&buf, " STRICT"); + if (proc->prosecdef) + appendStringInfoString(&buf, " SECURITY DEFINER"); + if (proc->proleakproof) + appendStringInfoString(&buf, " LEAKPROOF"); + + /* This code for the default cost and rows should match functioncmds.c */ + if (proc->prolang == INTERNALlanguageId || + proc->prolang == ClanguageId) + procost = 1; + else + procost = 100; + if (proc->procost != procost) + appendStringInfo(&buf, " COST %g", proc->procost); + + if (proc->prorows > 0 && proc->prorows != 1000) + appendStringInfo(&buf, " ROWS %g", proc->prorows); + + if (proc->prosupport) + { + Oid argtypes[1]; + + /* + * We should qualify the support function's name if it wouldn't be + * resolved by lookup in the current search path. + */ + argtypes[0] = INTERNALOID; + appendStringInfo(&buf, " SUPPORT %s", + generate_function_name(proc->prosupport, 1, + NIL, argtypes, + false, NULL, EXPR_KIND_NONE)); + } + + if (oldlen != buf.len) + appendStringInfoChar(&buf, '\n'); + + /* Emit any proconfig options, one per line */ + tmp = SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_proconfig, &isnull); + if (!isnull) + { + ArrayType *a = DatumGetArrayTypeP(tmp); + int i; + + Assert(ARR_ELEMTYPE(a) == TEXTOID); + Assert(ARR_NDIM(a) == 1); + Assert(ARR_LBOUND(a)[0] == 1); + + for (i = 1; i <= ARR_DIMS(a)[0]; i++) + { + Datum d; + + d = array_ref(a, 1, &i, + -1 /* varlenarray */ , + -1 /* TEXT's typlen */ , + false /* TEXT's typbyval */ , + TYPALIGN_INT /* TEXT's typalign */ , + &isnull); + if (!isnull) + { + char *configitem = TextDatumGetCString(d); + char *pos; + + pos = strchr(configitem, '='); + if (pos == NULL) + continue; + *pos++ = '\0'; + + appendStringInfo(&buf, " SET %s TO ", + quote_identifier(configitem)); + + /* + * Variables that are marked GUC_LIST_QUOTE were already fully + * quoted by flatten_set_variable_args() before they were put + * into the proconfig array. However, because the quoting + * rules used there aren't exactly like SQL's, we have to + * break the list value apart and then quote the elements as + * string literals. (The elements may be double-quoted as-is, + * but we can't just feed them to the SQL parser; it would do + * the wrong thing with elements that are zero-length or + * longer than NAMEDATALEN.) + * + * Variables that are not so marked should just be emitted as + * simple string literals. If the variable is not known to + * guc.c, we'll do that; this makes it unsafe to use + * GUC_LIST_QUOTE for extension variables. + */ + if (GetConfigOptionFlags(configitem, true) & GUC_LIST_QUOTE) + { + List *namelist; + ListCell *lc; + + /* Parse string into list of identifiers */ + if (!SplitGUCList(pos, ',', &namelist)) + { + /* this shouldn't fail really */ + elog(ERROR, "invalid list syntax in proconfig item"); + } + foreach(lc, namelist) + { + char *curname = (char *) lfirst(lc); + + simple_quote_literal(&buf, curname); + if (lnext(namelist, lc)) + appendStringInfoString(&buf, ", "); + } + } + else + simple_quote_literal(&buf, pos); + appendStringInfoChar(&buf, '\n'); + } + } + } + + /* And finally the function definition ... */ + (void) SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_prosqlbody, &isnull); + if (proc->prolang == SQLlanguageId && !isnull) + { + print_function_sqlbody(&buf, proctup); + } + else + { + appendStringInfoString(&buf, "AS "); + + tmp = SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_probin, &isnull); + if (!isnull) + { + simple_quote_literal(&buf, TextDatumGetCString(tmp)); + appendStringInfoString(&buf, ", "); /* assume prosrc isn't null */ + } + + tmp = SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_prosrc, &isnull); + if (isnull) + elog(ERROR, "null prosrc"); + prosrc = TextDatumGetCString(tmp); + + /* + * We always use dollar quoting. Figure out a suitable delimiter. + * + * Since the user is likely to be editing the function body string, we + * shouldn't use a short delimiter that he might easily create a + * conflict with. Hence prefer "$function$"/"$procedure$", but extend + * if needed. + */ + initStringInfo(&dq); + appendStringInfoChar(&dq, '$'); + appendStringInfoString(&dq, (isfunction ? "function" : "procedure")); + while (strstr(prosrc, dq.data) != NULL) + appendStringInfoChar(&dq, 'x'); + appendStringInfoChar(&dq, '$'); + + appendBinaryStringInfo(&buf, dq.data, dq.len); + appendStringInfoString(&buf, prosrc); + appendBinaryStringInfo(&buf, dq.data, dq.len); + } + + appendStringInfoChar(&buf, '\n'); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(string_to_text(buf.data)); +} + +/* + * pg_get_function_arguments + * Get a nicely-formatted list of arguments for a function. + * This is everything that would go between the parentheses in + * CREATE FUNCTION. + */ +Datum +pg_get_function_arguments(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + StringInfoData buf; + HeapTuple proctup; + + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + initStringInfo(&buf); + + (void) print_function_arguments(&buf, proctup, false, true); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(string_to_text(buf.data)); +} + +/* + * pg_get_function_identity_arguments + * Get a formatted list of arguments for a function. + * This is everything that would go between the parentheses in + * ALTER FUNCTION, etc. In particular, don't print defaults. + */ +Datum +pg_get_function_identity_arguments(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + StringInfoData buf; + HeapTuple proctup; + + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + initStringInfo(&buf); + + (void) print_function_arguments(&buf, proctup, false, false); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(string_to_text(buf.data)); +} + +/* + * pg_get_function_result + * Get a nicely-formatted version of the result type of a function. + * This is what would appear after RETURNS in CREATE FUNCTION. + */ +Datum +pg_get_function_result(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + StringInfoData buf; + HeapTuple proctup; + + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + if (((Form_pg_proc) GETSTRUCT(proctup))->prokind == PROKIND_PROCEDURE) + { + ReleaseSysCache(proctup); + PG_RETURN_NULL(); + } + + initStringInfo(&buf); + + print_function_rettype(&buf, proctup); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(string_to_text(buf.data)); +} + +/* + * Guts of pg_get_function_result: append the function's return type + * to the specified buffer. + */ +static void +print_function_rettype(StringInfo buf, HeapTuple proctup) +{ + Form_pg_proc proc = (Form_pg_proc) GETSTRUCT(proctup); + int ntabargs = 0; + StringInfoData rbuf; + + initStringInfo(&rbuf); + + if (proc->proretset) + { + /* It might be a table function; try to print the arguments */ + appendStringInfoString(&rbuf, "TABLE("); + ntabargs = print_function_arguments(&rbuf, proctup, true, false); + if (ntabargs > 0) + appendStringInfoChar(&rbuf, ')'); + else + resetStringInfo(&rbuf); + } + + if (ntabargs == 0) + { + /* Not a table function, so do the normal thing */ + if (proc->proretset) + appendStringInfoString(&rbuf, "SETOF "); + appendStringInfoString(&rbuf, format_type_be(proc->prorettype)); + } + + appendBinaryStringInfo(buf, rbuf.data, rbuf.len); +} + +/* + * Common code for pg_get_function_arguments and pg_get_function_result: + * append the desired subset of arguments to buf. We print only TABLE + * arguments when print_table_args is true, and all the others when it's false. + * We print argument defaults only if print_defaults is true. + * Function return value is the number of arguments printed. + */ +static int +print_function_arguments(StringInfo buf, HeapTuple proctup, + bool print_table_args, bool print_defaults) +{ + Form_pg_proc proc = (Form_pg_proc) GETSTRUCT(proctup); + int numargs; + Oid *argtypes; + char **argnames; + char *argmodes; + int insertorderbyat = -1; + int argsprinted; + int inputargno; + int nlackdefaults; + List *argdefaults = NIL; + ListCell *nextargdefault = NULL; + int i; + + numargs = get_func_arg_info(proctup, + &argtypes, &argnames, &argmodes); + + nlackdefaults = numargs; + if (print_defaults && proc->pronargdefaults > 0) + { + Datum proargdefaults; + bool isnull; + + proargdefaults = SysCacheGetAttr(PROCOID, proctup, + Anum_pg_proc_proargdefaults, + &isnull); + if (!isnull) + { + char *str; + + str = TextDatumGetCString(proargdefaults); + argdefaults = castNode(List, stringToNode(str)); + pfree(str); + nextargdefault = list_head(argdefaults); + /* nlackdefaults counts only *input* arguments lacking defaults */ + nlackdefaults = proc->pronargs - list_length(argdefaults); + } + } + + /* Check for special treatment of ordered-set aggregates */ + if (proc->prokind == PROKIND_AGGREGATE) + { + HeapTuple aggtup; + Form_pg_aggregate agg; + + aggtup = SearchSysCache1(AGGFNOID, proc->oid); + if (!HeapTupleIsValid(aggtup)) + elog(ERROR, "cache lookup failed for aggregate %u", + proc->oid); + agg = (Form_pg_aggregate) GETSTRUCT(aggtup); + if (AGGKIND_IS_ORDERED_SET(agg->aggkind)) + insertorderbyat = agg->aggnumdirectargs; + ReleaseSysCache(aggtup); + } + + argsprinted = 0; + inputargno = 0; + for (i = 0; i < numargs; i++) + { + Oid argtype = argtypes[i]; + char *argname = argnames ? argnames[i] : NULL; + char argmode = argmodes ? argmodes[i] : PROARGMODE_IN; + const char *modename; + bool isinput; + + switch (argmode) + { + case PROARGMODE_IN: + + /* + * For procedures, explicitly mark all argument modes, so as + * to avoid ambiguity with the SQL syntax for DROP PROCEDURE. + */ + if (proc->prokind == PROKIND_PROCEDURE) + modename = "IN "; + else + modename = ""; + isinput = true; + break; + case PROARGMODE_INOUT: + modename = "INOUT "; + isinput = true; + break; + case PROARGMODE_OUT: + modename = "OUT "; + isinput = false; + break; + case PROARGMODE_VARIADIC: + modename = "VARIADIC "; + isinput = true; + break; + case PROARGMODE_TABLE: + modename = ""; + isinput = false; + break; + default: + elog(ERROR, "invalid parameter mode '%c'", argmode); + modename = NULL; /* keep compiler quiet */ + isinput = false; + break; + } + if (isinput) + inputargno++; /* this is a 1-based counter */ + + if (print_table_args != (argmode == PROARGMODE_TABLE)) + continue; + + if (argsprinted == insertorderbyat) + { + if (argsprinted) + appendStringInfoChar(buf, ' '); + appendStringInfoString(buf, "ORDER BY "); + } + else if (argsprinted) + appendStringInfoString(buf, ", "); + + appendStringInfoString(buf, modename); + if (argname && argname[0]) + appendStringInfo(buf, "%s ", quote_identifier(argname)); + appendStringInfoString(buf, format_type_be(argtype)); + if (print_defaults && isinput && inputargno > nlackdefaults) + { + Node *expr; + + Assert(nextargdefault != NULL); + expr = (Node *) lfirst(nextargdefault); + nextargdefault = lnext(argdefaults, nextargdefault); + + appendStringInfo(buf, " DEFAULT %s", + deparse_expression(expr, NIL, false, false)); + } + argsprinted++; + + /* nasty hack: print the last arg twice for variadic ordered-set agg */ + if (argsprinted == insertorderbyat && i == numargs - 1) + { + i--; + /* aggs shouldn't have defaults anyway, but just to be sure ... */ + print_defaults = false; + } + } + + return argsprinted; +} + +static bool +is_input_argument(int nth, const char *argmodes) +{ + return (!argmodes + || argmodes[nth] == PROARGMODE_IN + || argmodes[nth] == PROARGMODE_INOUT + || argmodes[nth] == PROARGMODE_VARIADIC); +} + +/* + * Append used transformed types to specified buffer + */ +static void +print_function_trftypes(StringInfo buf, HeapTuple proctup) +{ + Oid *trftypes; + int ntypes; + + ntypes = get_func_trftypes(proctup, &trftypes); + if (ntypes > 0) + { + int i; + + appendStringInfoString(buf, " TRANSFORM "); + for (i = 0; i < ntypes; i++) + { + if (i != 0) + appendStringInfoString(buf, ", "); + appendStringInfo(buf, "FOR TYPE %s", format_type_be(trftypes[i])); + } + appendStringInfoChar(buf, '\n'); + } +} + +/* + * Get textual representation of a function argument's default value. The + * second argument of this function is the argument number among all arguments + * (i.e. proallargtypes, *not* proargtypes), starting with 1, because that's + * how information_schema.sql uses it. + */ +Datum +pg_get_function_arg_default(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + int32 nth_arg = PG_GETARG_INT32(1); + HeapTuple proctup; + Form_pg_proc proc; + int numargs; + Oid *argtypes; + char **argnames; + char *argmodes; + int i; + List *argdefaults; + Node *node; + char *str; + int nth_inputarg; + Datum proargdefaults; + bool isnull; + int nth_default; + + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + numargs = get_func_arg_info(proctup, &argtypes, &argnames, &argmodes); + if (nth_arg < 1 || nth_arg > numargs || !is_input_argument(nth_arg - 1, argmodes)) + { + ReleaseSysCache(proctup); + PG_RETURN_NULL(); + } + + nth_inputarg = 0; + for (i = 0; i < nth_arg; i++) + if (is_input_argument(i, argmodes)) + nth_inputarg++; + + proargdefaults = SysCacheGetAttr(PROCOID, proctup, + Anum_pg_proc_proargdefaults, + &isnull); + if (isnull) + { + ReleaseSysCache(proctup); + PG_RETURN_NULL(); + } + + str = TextDatumGetCString(proargdefaults); + argdefaults = castNode(List, stringToNode(str)); + pfree(str); + + proc = (Form_pg_proc) GETSTRUCT(proctup); + + /* + * Calculate index into proargdefaults: proargdefaults corresponds to the + * last N input arguments, where N = pronargdefaults. + */ + nth_default = nth_inputarg - 1 - (proc->pronargs - proc->pronargdefaults); + + if (nth_default < 0 || nth_default >= list_length(argdefaults)) + { + ReleaseSysCache(proctup); + PG_RETURN_NULL(); + } + node = list_nth(argdefaults, nth_default); + str = deparse_expression(node, NIL, false, false); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(string_to_text(str)); +} + +static void +print_function_sqlbody(StringInfo buf, HeapTuple proctup) +{ + int numargs; + Oid *argtypes; + char **argnames; + char *argmodes; + deparse_namespace dpns = {0}; + Datum tmp; + bool isnull; + Node *n; + + dpns.funcname = pstrdup(NameStr(((Form_pg_proc) GETSTRUCT(proctup))->proname)); + numargs = get_func_arg_info(proctup, + &argtypes, &argnames, &argmodes); + dpns.numargs = numargs; + dpns.argnames = argnames; + + tmp = SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_prosqlbody, &isnull); + Assert(!isnull); + n = stringToNode(TextDatumGetCString(tmp)); + + if (IsA(n, List)) + { + List *stmts; + ListCell *lc; + + stmts = linitial(castNode(List, n)); + + appendStringInfoString(buf, "BEGIN ATOMIC\n"); + + foreach(lc, stmts) + { + Query *query = lfirst_node(Query, lc); + + /* It seems advisable to get at least AccessShareLock on rels */ + AcquireRewriteLocks(query, false, false); + get_query_def(query, buf, list_make1(&dpns), NULL, false, + PRETTYFLAG_INDENT, WRAP_COLUMN_DEFAULT, 1); + appendStringInfoChar(buf, ';'); + appendStringInfoChar(buf, '\n'); + } + + appendStringInfoString(buf, "END"); + } + else + { + Query *query = castNode(Query, n); + + /* It seems advisable to get at least AccessShareLock on rels */ + AcquireRewriteLocks(query, false, false); + get_query_def(query, buf, list_make1(&dpns), NULL, false, + 0, WRAP_COLUMN_DEFAULT, 0); + } +} + +Datum +pg_get_function_sqlbody(PG_FUNCTION_ARGS) +{ + Oid funcid = PG_GETARG_OID(0); + StringInfoData buf; + HeapTuple proctup; + bool isnull; + + initStringInfo(&buf); + + /* Look up the function */ + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + PG_RETURN_NULL(); + + (void) SysCacheGetAttr(PROCOID, proctup, Anum_pg_proc_prosqlbody, &isnull); + if (isnull) + { + ReleaseSysCache(proctup); + PG_RETURN_NULL(); + } + + print_function_sqlbody(&buf, proctup); + + ReleaseSysCache(proctup); + + PG_RETURN_TEXT_P(cstring_to_text(buf.data)); +} + + +/* + * deparse_expression - General utility for deparsing expressions + * + * calls deparse_expression_pretty with all prettyPrinting disabled + */ +char * +deparse_expression(Node *expr, List *dpcontext, + bool forceprefix, bool showimplicit) +{ + return deparse_expression_pretty(expr, dpcontext, forceprefix, + showimplicit, 0, 0); +} + +/* ---------- + * deparse_expression_pretty - General utility for deparsing expressions + * + * expr is the node tree to be deparsed. It must be a transformed expression + * tree (ie, not the raw output of gram.y). + * + * dpcontext is a list of deparse_namespace nodes representing the context + * for interpreting Vars in the node tree. It can be NIL if no Vars are + * expected. + * + * forceprefix is true to force all Vars to be prefixed with their table names. + * + * showimplicit is true to force all implicit casts to be shown explicitly. + * + * Tries to pretty up the output according to prettyFlags and startIndent. + * + * The result is a palloc'd string. + * ---------- + */ +static char * +deparse_expression_pretty(Node *expr, List *dpcontext, + bool forceprefix, bool showimplicit, + int prettyFlags, int startIndent) +{ + StringInfoData buf; + deparse_context context; + + initStringInfo(&buf); + context.buf = &buf; + context.namespaces = dpcontext; + context.windowClause = NIL; + context.windowTList = NIL; + context.varprefix = forceprefix; + context.prettyFlags = prettyFlags; + context.wrapColumn = WRAP_COLUMN_DEFAULT; + context.indentLevel = startIndent; + context.special_exprkind = EXPR_KIND_NONE; + context.appendparents = NULL; + + get_rule_expr(expr, &context, showimplicit); + + return buf.data; +} + +/* ---------- + * deparse_context_for - Build deparse context for a single relation + * + * Given the reference name (alias) and OID of a relation, build deparsing + * context for an expression referencing only that relation (as varno 1, + * varlevelsup 0). This is sufficient for many uses of deparse_expression. + * ---------- + */ +List * +deparse_context_for(const char *aliasname, Oid relid) +{ + deparse_namespace *dpns; + RangeTblEntry *rte; + + dpns = (deparse_namespace *) palloc0(sizeof(deparse_namespace)); + + /* Build a minimal RTE for the rel */ + rte = makeNode(RangeTblEntry); + rte->rtekind = RTE_RELATION; + rte->relid = relid; + rte->relkind = RELKIND_RELATION; /* no need for exactness here */ + rte->rellockmode = AccessShareLock; + rte->alias = makeAlias(aliasname, NIL); + rte->eref = rte->alias; + rte->lateral = false; + rte->inh = false; + rte->inFromCl = true; + + /* Build one-element rtable */ + dpns->rtable = list_make1(rte); + dpns->subplans = NIL; + dpns->ctes = NIL; + dpns->appendrels = NULL; + set_rtable_names(dpns, NIL, NULL); + set_simple_column_names(dpns); + + /* Return a one-deep namespace stack */ + return list_make1(dpns); +} + +/* + * deparse_context_for_plan_tree - Build deparse context for a Plan tree + * + * When deparsing an expression in a Plan tree, we use the plan's rangetable + * to resolve names of simple Vars. The initialization of column names for + * this is rather expensive if the rangetable is large, and it'll be the same + * for every expression in the Plan tree; so we do it just once and re-use + * the result of this function for each expression. (Note that the result + * is not usable until set_deparse_context_plan() is applied to it.) + * + * In addition to the PlannedStmt, pass the per-RTE alias names + * assigned by a previous call to select_rtable_names_for_explain. + */ +List * +deparse_context_for_plan_tree(PlannedStmt *pstmt, List *rtable_names) +{ + deparse_namespace *dpns; + + dpns = (deparse_namespace *) palloc0(sizeof(deparse_namespace)); + + /* Initialize fields that stay the same across the whole plan tree */ + dpns->rtable = pstmt->rtable; + dpns->rtable_names = rtable_names; + dpns->subplans = pstmt->subplans; + dpns->ctes = NIL; + if (pstmt->appendRelations) + { + /* Set up the array, indexed by child relid */ + int ntables = list_length(dpns->rtable); + ListCell *lc; + + dpns->appendrels = (AppendRelInfo **) + palloc0((ntables + 1) * sizeof(AppendRelInfo *)); + foreach(lc, pstmt->appendRelations) + { + AppendRelInfo *appinfo = lfirst_node(AppendRelInfo, lc); + Index crelid = appinfo->child_relid; + + Assert(crelid > 0 && crelid <= ntables); + Assert(dpns->appendrels[crelid] == NULL); + dpns->appendrels[crelid] = appinfo; + } + } + else + dpns->appendrels = NULL; /* don't need it */ + + /* + * Set up column name aliases. We will get rather bogus results for join + * RTEs, but that doesn't matter because plan trees don't contain any join + * alias Vars. + */ + set_simple_column_names(dpns); + + /* Return a one-deep namespace stack */ + return list_make1(dpns); +} + +/* + * set_deparse_context_plan - Specify Plan node containing expression + * + * When deparsing an expression in a Plan tree, we might have to resolve + * OUTER_VAR, INNER_VAR, or INDEX_VAR references. To do this, the caller must + * provide the parent Plan node. Then OUTER_VAR and INNER_VAR references + * can be resolved by drilling down into the left and right child plans. + * Similarly, INDEX_VAR references can be resolved by reference to the + * indextlist given in a parent IndexOnlyScan node, or to the scan tlist in + * ForeignScan and CustomScan nodes. (Note that we don't currently support + * deparsing of indexquals in regular IndexScan or BitmapIndexScan nodes; + * for those, we can only deparse the indexqualorig fields, which won't + * contain INDEX_VAR Vars.) + * + * The ancestors list is a list of the Plan's parent Plan and SubPlan nodes, + * the most-closely-nested first. This is needed to resolve PARAM_EXEC + * Params. Note we assume that all the Plan nodes share the same rtable. + * + * Once this function has been called, deparse_expression() can be called on + * subsidiary expression(s) of the specified Plan node. To deparse + * expressions of a different Plan node in the same Plan tree, re-call this + * function to identify the new parent Plan node. + * + * The result is the same List passed in; this is a notational convenience. + */ +List * +set_deparse_context_plan(List *dpcontext, Plan *plan, List *ancestors) +{ + deparse_namespace *dpns; + + /* Should always have one-entry namespace list for Plan deparsing */ + Assert(list_length(dpcontext) == 1); + dpns = (deparse_namespace *) linitial(dpcontext); + + /* Set our attention on the specific plan node passed in */ + dpns->ancestors = ancestors; + set_deparse_plan(dpns, plan); + + return dpcontext; +} + +/* + * select_rtable_names_for_explain - Select RTE aliases for EXPLAIN + * + * Determine the relation aliases we'll use during an EXPLAIN operation. + * This is just a frontend to set_rtable_names. We have to expose the aliases + * to EXPLAIN because EXPLAIN needs to know the right alias names to print. + */ +List * +select_rtable_names_for_explain(List *rtable, Bitmapset *rels_used) +{ + deparse_namespace dpns; + + memset(&dpns, 0, sizeof(dpns)); + dpns.rtable = rtable; + dpns.subplans = NIL; + dpns.ctes = NIL; + dpns.appendrels = NULL; + set_rtable_names(&dpns, NIL, rels_used); + /* We needn't bother computing column aliases yet */ + + return dpns.rtable_names; +} + +/* + * set_rtable_names: select RTE aliases to be used in printing a query + * + * We fill in dpns->rtable_names with a list of names that is one-for-one with + * the already-filled dpns->rtable list. Each RTE name is unique among those + * in the new namespace plus any ancestor namespaces listed in + * parent_namespaces. + * + * If rels_used isn't NULL, only RTE indexes listed in it are given aliases. + * + * Note that this function is only concerned with relation names, not column + * names. + */ +static void +set_rtable_names(deparse_namespace *dpns, List *parent_namespaces, + Bitmapset *rels_used) +{ + HASHCTL hash_ctl; + HTAB *names_hash; + NameHashEntry *hentry; + bool found; + int rtindex; + ListCell *lc; + + dpns->rtable_names = NIL; + /* nothing more to do if empty rtable */ + if (dpns->rtable == NIL) + return; + + /* + * We use a hash table to hold known names, so that this process is O(N) + * not O(N^2) for N names. + */ + hash_ctl.keysize = NAMEDATALEN; + hash_ctl.entrysize = sizeof(NameHashEntry); + hash_ctl.hcxt = CurrentMemoryContext; + names_hash = hash_create("set_rtable_names names", + list_length(dpns->rtable), + &hash_ctl, + HASH_ELEM | HASH_STRINGS | HASH_CONTEXT); + + /* Preload the hash table with names appearing in parent_namespaces */ + foreach(lc, parent_namespaces) + { + deparse_namespace *olddpns = (deparse_namespace *) lfirst(lc); + ListCell *lc2; + + foreach(lc2, olddpns->rtable_names) + { + char *oldname = (char *) lfirst(lc2); + + if (oldname == NULL) + continue; + hentry = (NameHashEntry *) hash_search(names_hash, + oldname, + HASH_ENTER, + &found); + /* we do not complain about duplicate names in parent namespaces */ + hentry->counter = 0; + } + } + + /* Now we can scan the rtable */ + rtindex = 1; + foreach(lc, dpns->rtable) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + char *refname; + + /* Just in case this takes an unreasonable amount of time ... */ + CHECK_FOR_INTERRUPTS(); + + if (rels_used && !bms_is_member(rtindex, rels_used)) + { + /* Ignore unreferenced RTE */ + refname = NULL; + } + else if (rte->alias) + { + /* If RTE has a user-defined alias, prefer that */ + refname = rte->alias->aliasname; + } + else if (rte->rtekind == RTE_RELATION) + { + /* Use the current actual name of the relation */ + refname = get_rel_name(rte->relid); + } + else if (rte->rtekind == RTE_JOIN) + { + /* Unnamed join has no refname */ + refname = NULL; + } + else + { + /* Otherwise use whatever the parser assigned */ + refname = rte->eref->aliasname; + } + + /* + * If the selected name isn't unique, append digits to make it so, and + * make a new hash entry for it once we've got a unique name. For a + * very long input name, we might have to truncate to stay within + * NAMEDATALEN. + */ + if (refname) + { + hentry = (NameHashEntry *) hash_search(names_hash, + refname, + HASH_ENTER, + &found); + if (found) + { + /* Name already in use, must choose a new one */ + int refnamelen = strlen(refname); + char *modname = (char *) palloc(refnamelen + 16); + NameHashEntry *hentry2; + + do + { + hentry->counter++; + for (;;) + { + memcpy(modname, refname, refnamelen); + sprintf(modname + refnamelen, "_%d", hentry->counter); + if (strlen(modname) < NAMEDATALEN) + break; + /* drop chars from refname to keep all the digits */ + refnamelen = pg_mbcliplen(refname, refnamelen, + refnamelen - 1); + } + hentry2 = (NameHashEntry *) hash_search(names_hash, + modname, + HASH_ENTER, + &found); + } while (found); + hentry2->counter = 0; /* init new hash entry */ + refname = modname; + } + else + { + /* Name not previously used, need only initialize hentry */ + hentry->counter = 0; + } + } + + dpns->rtable_names = lappend(dpns->rtable_names, refname); + rtindex++; + } + + hash_destroy(names_hash); +} + +/* + * set_deparse_for_query: set up deparse_namespace for deparsing a Query tree + * + * For convenience, this is defined to initialize the deparse_namespace struct + * from scratch. + */ +static void +set_deparse_for_query(deparse_namespace *dpns, Query *query, + List *parent_namespaces) +{ + ListCell *lc; + ListCell *lc2; + + /* Initialize *dpns and fill rtable/ctes links */ + memset(dpns, 0, sizeof(deparse_namespace)); + dpns->rtable = query->rtable; + dpns->subplans = NIL; + dpns->ctes = query->cteList; + dpns->appendrels = NULL; + + /* Assign a unique relation alias to each RTE */ + set_rtable_names(dpns, parent_namespaces, NULL); + + /* Initialize dpns->rtable_columns to contain zeroed structs */ + dpns->rtable_columns = NIL; + while (list_length(dpns->rtable_columns) < list_length(dpns->rtable)) + dpns->rtable_columns = lappend(dpns->rtable_columns, + palloc0(sizeof(deparse_columns))); + + /* If it's a utility query, it won't have a jointree */ + if (query->jointree) + { + /* Detect whether global uniqueness of USING names is needed */ + dpns->unique_using = + has_dangerous_join_using(dpns, (Node *) query->jointree); + + /* + * Select names for columns merged by USING, via a recursive pass over + * the query jointree. + */ + set_using_names(dpns, (Node *) query->jointree, NIL); + } + + /* + * Now assign remaining column aliases for each RTE. We do this in a + * linear scan of the rtable, so as to process RTEs whether or not they + * are in the jointree (we mustn't miss NEW.*, INSERT target relations, + * etc). JOIN RTEs must be processed after their children, but this is + * okay because they appear later in the rtable list than their children + * (cf Asserts in identify_join_columns()). + */ + forboth(lc, dpns->rtable, lc2, dpns->rtable_columns) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + deparse_columns *colinfo = (deparse_columns *) lfirst(lc2); + + if (rte->rtekind == RTE_JOIN) + set_join_column_names(dpns, rte, colinfo); + else + set_relation_column_names(dpns, rte, colinfo); + } +} + +/* + * set_simple_column_names: fill in column aliases for non-query situations + * + * This handles EXPLAIN and cases where we only have relation RTEs. Without + * a join tree, we can't do anything smart about join RTEs, but we don't + * need to (note that EXPLAIN should never see join alias Vars anyway). + * If we do hit a join RTE we'll just process it like a non-table base RTE. + */ +static void +set_simple_column_names(deparse_namespace *dpns) +{ + ListCell *lc; + ListCell *lc2; + + /* Initialize dpns->rtable_columns to contain zeroed structs */ + dpns->rtable_columns = NIL; + while (list_length(dpns->rtable_columns) < list_length(dpns->rtable)) + dpns->rtable_columns = lappend(dpns->rtable_columns, + palloc0(sizeof(deparse_columns))); + + /* Assign unique column aliases within each RTE */ + forboth(lc, dpns->rtable, lc2, dpns->rtable_columns) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + deparse_columns *colinfo = (deparse_columns *) lfirst(lc2); + + set_relation_column_names(dpns, rte, colinfo); + } +} + +/* + * has_dangerous_join_using: search jointree for unnamed JOIN USING + * + * Merged columns of a JOIN USING may act differently from either of the input + * columns, either because they are merged with COALESCE (in a FULL JOIN) or + * because an implicit coercion of the underlying input column is required. + * In such a case the column must be referenced as a column of the JOIN not as + * a column of either input. And this is problematic if the join is unnamed + * (alias-less): we cannot qualify the column's name with an RTE name, since + * there is none. (Forcibly assigning an alias to the join is not a solution, + * since that will prevent legal references to tables below the join.) + * To ensure that every column in the query is unambiguously referenceable, + * we must assign such merged columns names that are globally unique across + * the whole query, aliasing other columns out of the way as necessary. + * + * Because the ensuing re-aliasing is fairly damaging to the readability of + * the query, we don't do this unless we have to. So, we must pre-scan + * the join tree to see if we have to, before starting set_using_names(). + */ +static bool +has_dangerous_join_using(deparse_namespace *dpns, Node *jtnode) +{ + if (IsA(jtnode, RangeTblRef)) + { + /* nothing to do here */ + } + else if (IsA(jtnode, FromExpr)) + { + FromExpr *f = (FromExpr *) jtnode; + ListCell *lc; + + foreach(lc, f->fromlist) + { + if (has_dangerous_join_using(dpns, (Node *) lfirst(lc))) + return true; + } + } + else if (IsA(jtnode, JoinExpr)) + { + JoinExpr *j = (JoinExpr *) jtnode; + + /* Is it an unnamed JOIN with USING? */ + if (j->alias == NULL && j->usingClause) + { + /* + * Yes, so check each join alias var to see if any of them are not + * simple references to underlying columns. If so, we have a + * dangerous situation and must pick unique aliases. + */ + RangeTblEntry *jrte = rt_fetch(j->rtindex, dpns->rtable); + + /* We need only examine the merged columns */ + for (int i = 0; i < jrte->joinmergedcols; i++) + { + Node *aliasvar = list_nth(jrte->joinaliasvars, i); + + if (!IsA(aliasvar, Var)) + return true; + } + } + + /* Nope, but inspect children */ + if (has_dangerous_join_using(dpns, j->larg)) + return true; + if (has_dangerous_join_using(dpns, j->rarg)) + return true; + } + else + elog(ERROR, "unrecognized node type: %d", + (int) nodeTag(jtnode)); + return false; +} + +/* + * set_using_names: select column aliases to be used for merged USING columns + * + * We do this during a recursive descent of the query jointree. + * dpns->unique_using must already be set to determine the global strategy. + * + * Column alias info is saved in the dpns->rtable_columns list, which is + * assumed to be filled with pre-zeroed deparse_columns structs. + * + * parentUsing is a list of all USING aliases assigned in parent joins of + * the current jointree node. (The passed-in list must not be modified.) + */ +static void +set_using_names(deparse_namespace *dpns, Node *jtnode, List *parentUsing) +{ + if (IsA(jtnode, RangeTblRef)) + { + /* nothing to do now */ + } + else if (IsA(jtnode, FromExpr)) + { + FromExpr *f = (FromExpr *) jtnode; + ListCell *lc; + + foreach(lc, f->fromlist) + set_using_names(dpns, (Node *) lfirst(lc), parentUsing); + } + else if (IsA(jtnode, JoinExpr)) + { + JoinExpr *j = (JoinExpr *) jtnode; + RangeTblEntry *rte = rt_fetch(j->rtindex, dpns->rtable); + deparse_columns *colinfo = deparse_columns_fetch(j->rtindex, dpns); + int *leftattnos; + int *rightattnos; + deparse_columns *leftcolinfo; + deparse_columns *rightcolinfo; + int i; + ListCell *lc; + + /* Get info about the shape of the join */ + identify_join_columns(j, rte, colinfo); + leftattnos = colinfo->leftattnos; + rightattnos = colinfo->rightattnos; + + /* Look up the not-yet-filled-in child deparse_columns structs */ + leftcolinfo = deparse_columns_fetch(colinfo->leftrti, dpns); + rightcolinfo = deparse_columns_fetch(colinfo->rightrti, dpns); + + /* + * If this join is unnamed, then we cannot substitute new aliases at + * this level, so any name requirements pushed down to here must be + * pushed down again to the children. + */ + if (rte->alias == NULL) + { + for (i = 0; i < colinfo->num_cols; i++) + { + char *colname = colinfo->colnames[i]; + + if (colname == NULL) + continue; + + /* Push down to left column, unless it's a system column */ + if (leftattnos[i] > 0) + { + expand_colnames_array_to(leftcolinfo, leftattnos[i]); + leftcolinfo->colnames[leftattnos[i] - 1] = colname; + } + + /* Same on the righthand side */ + if (rightattnos[i] > 0) + { + expand_colnames_array_to(rightcolinfo, rightattnos[i]); + rightcolinfo->colnames[rightattnos[i] - 1] = colname; + } + } + } + + /* + * If there's a USING clause, select the USING column names and push + * those names down to the children. We have two strategies: + * + * If dpns->unique_using is true, we force all USING names to be + * unique across the whole query level. In principle we'd only need + * the names of dangerous USING columns to be globally unique, but to + * safely assign all USING names in a single pass, we have to enforce + * the same uniqueness rule for all of them. However, if a USING + * column's name has been pushed down from the parent, we should use + * it as-is rather than making a uniqueness adjustment. This is + * necessary when we're at an unnamed join, and it creates no risk of + * ambiguity. Also, if there's a user-written output alias for a + * merged column, we prefer to use that rather than the input name; + * this simplifies the logic and seems likely to lead to less aliasing + * overall. + * + * If dpns->unique_using is false, we only need USING names to be + * unique within their own join RTE. We still need to honor + * pushed-down names, though. + * + * Though significantly different in results, these two strategies are + * implemented by the same code, with only the difference of whether + * to put assigned names into dpns->using_names. + */ + if (j->usingClause) + { + /* Copy the input parentUsing list so we don't modify it */ + parentUsing = list_copy(parentUsing); + + /* USING names must correspond to the first join output columns */ + expand_colnames_array_to(colinfo, list_length(j->usingClause)); + i = 0; + foreach(lc, j->usingClause) + { + char *colname = strVal(lfirst(lc)); + + /* Assert it's a merged column */ + Assert(leftattnos[i] != 0 && rightattnos[i] != 0); + + /* Adopt passed-down name if any, else select unique name */ + if (colinfo->colnames[i] != NULL) + colname = colinfo->colnames[i]; + else + { + /* Prefer user-written output alias if any */ + if (rte->alias && i < list_length(rte->alias->colnames)) + colname = strVal(list_nth(rte->alias->colnames, i)); + /* Make it appropriately unique */ + colname = make_colname_unique(colname, dpns, colinfo); + if (dpns->unique_using) + dpns->using_names = lappend(dpns->using_names, + colname); + /* Save it as output column name, too */ + colinfo->colnames[i] = colname; + } + + /* Remember selected names for use later */ + colinfo->usingNames = lappend(colinfo->usingNames, colname); + parentUsing = lappend(parentUsing, colname); + + /* Push down to left column, unless it's a system column */ + if (leftattnos[i] > 0) + { + expand_colnames_array_to(leftcolinfo, leftattnos[i]); + leftcolinfo->colnames[leftattnos[i] - 1] = colname; + } + + /* Same on the righthand side */ + if (rightattnos[i] > 0) + { + expand_colnames_array_to(rightcolinfo, rightattnos[i]); + rightcolinfo->colnames[rightattnos[i] - 1] = colname; + } + + i++; + } + } + + /* Mark child deparse_columns structs with correct parentUsing info */ + leftcolinfo->parentUsing = parentUsing; + rightcolinfo->parentUsing = parentUsing; + + /* Now recursively assign USING column names in children */ + set_using_names(dpns, j->larg, parentUsing); + set_using_names(dpns, j->rarg, parentUsing); + } + else + elog(ERROR, "unrecognized node type: %d", + (int) nodeTag(jtnode)); +} + +/* + * set_relation_column_names: select column aliases for a non-join RTE + * + * Column alias info is saved in *colinfo, which is assumed to be pre-zeroed. + * If any colnames entries are already filled in, those override local + * choices. + */ +static void +set_relation_column_names(deparse_namespace *dpns, RangeTblEntry *rte, + deparse_columns *colinfo) +{ + int ncolumns; + char **real_colnames; + bool changed_any; + int noldcolumns; + int i; + int j; + + /* + * Construct an array of the current "real" column names of the RTE. + * real_colnames[] will be indexed by physical column number, with NULL + * entries for dropped columns. + */ + if (rte->rtekind == RTE_RELATION) + { + /* Relation --- look to the system catalogs for up-to-date info */ + Relation rel; + TupleDesc tupdesc; + + rel = relation_open(rte->relid, AccessShareLock); + tupdesc = RelationGetDescr(rel); + + ncolumns = tupdesc->natts; + real_colnames = (char **) palloc(ncolumns * sizeof(char *)); + + for (i = 0; i < ncolumns; i++) + { + Form_pg_attribute attr = TupleDescAttr(tupdesc, i); + + if (attr->attisdropped) + real_colnames[i] = NULL; + else + real_colnames[i] = pstrdup(NameStr(attr->attname)); + } + relation_close(rel, AccessShareLock); + } + else + { + /* Otherwise get the column names from eref or expandRTE() */ + List *colnames; + ListCell *lc; + + /* + * Functions returning composites have the annoying property that some + * of the composite type's columns might have been dropped since the + * query was parsed. If possible, use expandRTE() to handle that + * case, since it has the tedious logic needed to find out about + * dropped columns. However, if we're explaining a plan, then we + * don't have rte->functions because the planner thinks that won't be + * needed later, and that breaks expandRTE(). So in that case we have + * to rely on rte->eref, which may lead us to report a dropped + * column's old name; that seems close enough for EXPLAIN's purposes. + * + * For non-RELATION, non-FUNCTION RTEs, we can just look at rte->eref, + * which should be sufficiently up-to-date: no other RTE types can + * have columns get dropped from under them after parsing. + */ + if (rte->rtekind == RTE_FUNCTION && rte->functions != NIL) + { + /* Since we're not creating Vars, rtindex etc. don't matter */ + expandRTE(rte, 1, 0, -1, true /* include dropped */ , + &colnames, NULL); + } + else + colnames = rte->eref->colnames; + + ncolumns = list_length(colnames); + real_colnames = (char **) palloc(ncolumns * sizeof(char *)); + + i = 0; + foreach(lc, colnames) + { + /* + * If the column name we find here is an empty string, then it's a + * dropped column, so change to NULL. + */ + char *cname = strVal(lfirst(lc)); + + if (cname[0] == '\0') + cname = NULL; + real_colnames[i] = cname; + i++; + } + } + + /* + * Ensure colinfo->colnames has a slot for each column. (It could be long + * enough already, if we pushed down a name for the last column.) Note: + * it's possible that there are now more columns than there were when the + * query was parsed, ie colnames could be longer than rte->eref->colnames. + * We must assign unique aliases to the new columns too, else there could + * be unresolved conflicts when the view/rule is reloaded. + */ + expand_colnames_array_to(colinfo, ncolumns); + Assert(colinfo->num_cols == ncolumns); + + /* + * Make sufficiently large new_colnames and is_new_col arrays, too. + * + * Note: because we leave colinfo->num_new_cols zero until after the loop, + * colname_is_unique will not consult that array, which is fine because it + * would only be duplicate effort. + */ + colinfo->new_colnames = (char **) palloc(ncolumns * sizeof(char *)); + colinfo->is_new_col = (bool *) palloc(ncolumns * sizeof(bool)); + + /* + * Scan the columns, select a unique alias for each one, and store it in + * colinfo->colnames and colinfo->new_colnames. The former array has NULL + * entries for dropped columns, the latter omits them. Also mark + * new_colnames entries as to whether they are new since parse time; this + * is the case for entries beyond the length of rte->eref->colnames. + */ + noldcolumns = list_length(rte->eref->colnames); + changed_any = false; + j = 0; + for (i = 0; i < ncolumns; i++) + { + char *real_colname = real_colnames[i]; + char *colname = colinfo->colnames[i]; + + /* Skip dropped columns */ + if (real_colname == NULL) + { + Assert(colname == NULL); /* colnames[i] is already NULL */ + continue; + } + + /* If alias already assigned, that's what to use */ + if (colname == NULL) + { + /* If user wrote an alias, prefer that over real column name */ + if (rte->alias && i < list_length(rte->alias->colnames)) + colname = strVal(list_nth(rte->alias->colnames, i)); + else + colname = real_colname; + + /* Unique-ify and insert into colinfo */ + colname = make_colname_unique(colname, dpns, colinfo); + + colinfo->colnames[i] = colname; + } + + /* Put names of non-dropped columns in new_colnames[] too */ + colinfo->new_colnames[j] = colname; + /* And mark them as new or not */ + colinfo->is_new_col[j] = (i >= noldcolumns); + j++; + + /* Remember if any assigned aliases differ from "real" name */ + if (!changed_any && strcmp(colname, real_colname) != 0) + changed_any = true; + } + + /* + * Set correct length for new_colnames[] array. (Note: if columns have + * been added, colinfo->num_cols includes them, which is not really quite + * right but is harmless, since any new columns must be at the end where + * they won't affect varattnos of pre-existing columns.) + */ + colinfo->num_new_cols = j; + + /* + * For a relation RTE, we need only print the alias column names if any + * are different from the underlying "real" names. For a function RTE, + * always emit a complete column alias list; this is to protect against + * possible instability of the default column names (eg, from altering + * parameter names). For tablefunc RTEs, we never print aliases, because + * the column names are part of the clause itself. For other RTE types, + * print if we changed anything OR if there were user-written column + * aliases (since the latter would be part of the underlying "reality"). + */ + if (rte->rtekind == RTE_RELATION) + colinfo->printaliases = changed_any; + else if (rte->rtekind == RTE_FUNCTION) + colinfo->printaliases = true; + else if (rte->rtekind == RTE_TABLEFUNC) + colinfo->printaliases = false; + else if (rte->alias && rte->alias->colnames != NIL) + colinfo->printaliases = true; + else + colinfo->printaliases = changed_any; +} + +/* + * set_join_column_names: select column aliases for a join RTE + * + * Column alias info is saved in *colinfo, which is assumed to be pre-zeroed. + * If any colnames entries are already filled in, those override local + * choices. Also, names for USING columns were already chosen by + * set_using_names(). We further expect that column alias selection has been + * completed for both input RTEs. + */ +static void +set_join_column_names(deparse_namespace *dpns, RangeTblEntry *rte, + deparse_columns *colinfo) +{ + deparse_columns *leftcolinfo; + deparse_columns *rightcolinfo; + bool changed_any; + int noldcolumns; + int nnewcolumns; + Bitmapset *leftmerged = NULL; + Bitmapset *rightmerged = NULL; + int i; + int j; + int ic; + int jc; + + /* Look up the previously-filled-in child deparse_columns structs */ + leftcolinfo = deparse_columns_fetch(colinfo->leftrti, dpns); + rightcolinfo = deparse_columns_fetch(colinfo->rightrti, dpns); + + /* + * Ensure colinfo->colnames has a slot for each column. (It could be long + * enough already, if we pushed down a name for the last column.) Note: + * it's possible that one or both inputs now have more columns than there + * were when the query was parsed, but we'll deal with that below. We + * only need entries in colnames for pre-existing columns. + */ + noldcolumns = list_length(rte->eref->colnames); + expand_colnames_array_to(colinfo, noldcolumns); + Assert(colinfo->num_cols == noldcolumns); + + /* + * Scan the join output columns, select an alias for each one, and store + * it in colinfo->colnames. If there are USING columns, set_using_names() + * already selected their names, so we can start the loop at the first + * non-merged column. + */ + changed_any = false; + for (i = list_length(colinfo->usingNames); i < noldcolumns; i++) + { + char *colname = colinfo->colnames[i]; + char *real_colname; + + /* Join column must refer to at least one input column */ + Assert(colinfo->leftattnos[i] != 0 || colinfo->rightattnos[i] != 0); + + /* Get the child column name */ + if (colinfo->leftattnos[i] > 0) + real_colname = leftcolinfo->colnames[colinfo->leftattnos[i] - 1]; + else if (colinfo->rightattnos[i] > 0) + real_colname = rightcolinfo->colnames[colinfo->rightattnos[i] - 1]; + else + { + /* We're joining system columns --- use eref name */ + real_colname = strVal(list_nth(rte->eref->colnames, i)); + } + + /* If child col has been dropped, no need to assign a join colname */ + if (real_colname == NULL) + { + colinfo->colnames[i] = NULL; + continue; + } + + /* In an unnamed join, just report child column names as-is */ + if (rte->alias == NULL) + { + colinfo->colnames[i] = real_colname; + continue; + } + + /* If alias already assigned, that's what to use */ + if (colname == NULL) + { + /* If user wrote an alias, prefer that over real column name */ + if (rte->alias && i < list_length(rte->alias->colnames)) + colname = strVal(list_nth(rte->alias->colnames, i)); + else + colname = real_colname; + + /* Unique-ify and insert into colinfo */ + colname = make_colname_unique(colname, dpns, colinfo); + + colinfo->colnames[i] = colname; + } + + /* Remember if any assigned aliases differ from "real" name */ + if (!changed_any && strcmp(colname, real_colname) != 0) + changed_any = true; + } + + /* + * Calculate number of columns the join would have if it were re-parsed + * now, and create storage for the new_colnames and is_new_col arrays. + * + * Note: colname_is_unique will be consulting new_colnames[] during the + * loops below, so its not-yet-filled entries must be zeroes. + */ + nnewcolumns = leftcolinfo->num_new_cols + rightcolinfo->num_new_cols - + list_length(colinfo->usingNames); + colinfo->num_new_cols = nnewcolumns; + colinfo->new_colnames = (char **) palloc0(nnewcolumns * sizeof(char *)); + colinfo->is_new_col = (bool *) palloc0(nnewcolumns * sizeof(bool)); + + /* + * Generating the new_colnames array is a bit tricky since any new columns + * added since parse time must be inserted in the right places. This code + * must match the parser, which will order a join's columns as merged + * columns first (in USING-clause order), then non-merged columns from the + * left input (in attnum order), then non-merged columns from the right + * input (ditto). If one of the inputs is itself a join, its columns will + * be ordered according to the same rule, which means newly-added columns + * might not be at the end. We can figure out what's what by consulting + * the leftattnos and rightattnos arrays plus the input is_new_col arrays. + * + * In these loops, i indexes leftattnos/rightattnos (so it's join varattno + * less one), j indexes new_colnames/is_new_col, and ic/jc have similar + * meanings for the current child RTE. + */ + + /* Handle merged columns; they are first and can't be new */ + i = j = 0; + while (i < noldcolumns && + colinfo->leftattnos[i] != 0 && + colinfo->rightattnos[i] != 0) + { + /* column name is already determined and known unique */ + colinfo->new_colnames[j] = colinfo->colnames[i]; + colinfo->is_new_col[j] = false; + + /* build bitmapsets of child attnums of merged columns */ + if (colinfo->leftattnos[i] > 0) + leftmerged = bms_add_member(leftmerged, colinfo->leftattnos[i]); + if (colinfo->rightattnos[i] > 0) + rightmerged = bms_add_member(rightmerged, colinfo->rightattnos[i]); + + i++, j++; + } + + /* Handle non-merged left-child columns */ + ic = 0; + for (jc = 0; jc < leftcolinfo->num_new_cols; jc++) + { + char *child_colname = leftcolinfo->new_colnames[jc]; + + if (!leftcolinfo->is_new_col[jc]) + { + /* Advance ic to next non-dropped old column of left child */ + while (ic < leftcolinfo->num_cols && + leftcolinfo->colnames[ic] == NULL) + ic++; + Assert(ic < leftcolinfo->num_cols); + ic++; + /* If it is a merged column, we already processed it */ + if (bms_is_member(ic, leftmerged)) + continue; + /* Else, advance i to the corresponding existing join column */ + while (i < colinfo->num_cols && + colinfo->colnames[i] == NULL) + i++; + Assert(i < colinfo->num_cols); + Assert(ic == colinfo->leftattnos[i]); + /* Use the already-assigned name of this column */ + colinfo->new_colnames[j] = colinfo->colnames[i]; + i++; + } + else + { + /* + * Unique-ify the new child column name and assign, unless we're + * in an unnamed join, in which case just copy + */ + if (rte->alias != NULL) + { + colinfo->new_colnames[j] = + make_colname_unique(child_colname, dpns, colinfo); + if (!changed_any && + strcmp(colinfo->new_colnames[j], child_colname) != 0) + changed_any = true; + } + else + colinfo->new_colnames[j] = child_colname; + } + + colinfo->is_new_col[j] = leftcolinfo->is_new_col[jc]; + j++; + } + + /* Handle non-merged right-child columns in exactly the same way */ + ic = 0; + for (jc = 0; jc < rightcolinfo->num_new_cols; jc++) + { + char *child_colname = rightcolinfo->new_colnames[jc]; + + if (!rightcolinfo->is_new_col[jc]) + { + /* Advance ic to next non-dropped old column of right child */ + while (ic < rightcolinfo->num_cols && + rightcolinfo->colnames[ic] == NULL) + ic++; + Assert(ic < rightcolinfo->num_cols); + ic++; + /* If it is a merged column, we already processed it */ + if (bms_is_member(ic, rightmerged)) + continue; + /* Else, advance i to the corresponding existing join column */ + while (i < colinfo->num_cols && + colinfo->colnames[i] == NULL) + i++; + Assert(i < colinfo->num_cols); + Assert(ic == colinfo->rightattnos[i]); + /* Use the already-assigned name of this column */ + colinfo->new_colnames[j] = colinfo->colnames[i]; + i++; + } + else + { + /* + * Unique-ify the new child column name and assign, unless we're + * in an unnamed join, in which case just copy + */ + if (rte->alias != NULL) + { + colinfo->new_colnames[j] = + make_colname_unique(child_colname, dpns, colinfo); + if (!changed_any && + strcmp(colinfo->new_colnames[j], child_colname) != 0) + changed_any = true; + } + else + colinfo->new_colnames[j] = child_colname; + } + + colinfo->is_new_col[j] = rightcolinfo->is_new_col[jc]; + j++; + } + + /* Assert we processed the right number of columns */ +#ifdef USE_ASSERT_CHECKING + while (i < colinfo->num_cols && colinfo->colnames[i] == NULL) + i++; + Assert(i == colinfo->num_cols); + Assert(j == nnewcolumns); +#endif + + /* + * For a named join, print column aliases if we changed any from the child + * names. Unnamed joins cannot print aliases. + */ + if (rte->alias != NULL) + colinfo->printaliases = changed_any; + else + colinfo->printaliases = false; +} + +/* + * colname_is_unique: is colname distinct from already-chosen column names? + * + * dpns is query-wide info, colinfo is for the column's RTE + */ +static bool +colname_is_unique(const char *colname, deparse_namespace *dpns, + deparse_columns *colinfo) +{ + int i; + ListCell *lc; + + /* Check against already-assigned column aliases within RTE */ + for (i = 0; i < colinfo->num_cols; i++) + { + char *oldname = colinfo->colnames[i]; + + if (oldname && strcmp(oldname, colname) == 0) + return false; + } + + /* + * If we're building a new_colnames array, check that too (this will be + * partially but not completely redundant with the previous checks) + */ + for (i = 0; i < colinfo->num_new_cols; i++) + { + char *oldname = colinfo->new_colnames[i]; + + if (oldname && strcmp(oldname, colname) == 0) + return false; + } + + /* Also check against USING-column names that must be globally unique */ + foreach(lc, dpns->using_names) + { + char *oldname = (char *) lfirst(lc); + + if (strcmp(oldname, colname) == 0) + return false; + } + + /* Also check against names already assigned for parent-join USING cols */ + foreach(lc, colinfo->parentUsing) + { + char *oldname = (char *) lfirst(lc); + + if (strcmp(oldname, colname) == 0) + return false; + } + + return true; +} + +/* + * make_colname_unique: modify colname if necessary to make it unique + * + * dpns is query-wide info, colinfo is for the column's RTE + */ +static char * +make_colname_unique(char *colname, deparse_namespace *dpns, + deparse_columns *colinfo) +{ + /* + * If the selected name isn't unique, append digits to make it so. For a + * very long input name, we might have to truncate to stay within + * NAMEDATALEN. + */ + if (!colname_is_unique(colname, dpns, colinfo)) + { + int colnamelen = strlen(colname); + char *modname = (char *) palloc(colnamelen + 16); + int i = 0; + + do + { + i++; + for (;;) + { + memcpy(modname, colname, colnamelen); + sprintf(modname + colnamelen, "_%d", i); + if (strlen(modname) < NAMEDATALEN) + break; + /* drop chars from colname to keep all the digits */ + colnamelen = pg_mbcliplen(colname, colnamelen, + colnamelen - 1); + } + } while (!colname_is_unique(modname, dpns, colinfo)); + colname = modname; + } + return colname; +} + +/* + * expand_colnames_array_to: make colinfo->colnames at least n items long + * + * Any added array entries are initialized to zero. + */ +static void +expand_colnames_array_to(deparse_columns *colinfo, int n) +{ + if (n > colinfo->num_cols) + { + if (colinfo->colnames == NULL) + colinfo->colnames = (char **) palloc0(n * sizeof(char *)); + else + { + colinfo->colnames = (char **) repalloc(colinfo->colnames, + n * sizeof(char *)); + memset(colinfo->colnames + colinfo->num_cols, 0, + (n - colinfo->num_cols) * sizeof(char *)); + } + colinfo->num_cols = n; + } +} + +/* + * identify_join_columns: figure out where columns of a join come from + * + * Fills the join-specific fields of the colinfo struct, except for + * usingNames which is filled later. + */ +static void +identify_join_columns(JoinExpr *j, RangeTblEntry *jrte, + deparse_columns *colinfo) +{ + int numjoincols; + int jcolno; + int rcolno; + ListCell *lc; + + /* Extract left/right child RT indexes */ + if (IsA(j->larg, RangeTblRef)) + colinfo->leftrti = ((RangeTblRef *) j->larg)->rtindex; + else if (IsA(j->larg, JoinExpr)) + colinfo->leftrti = ((JoinExpr *) j->larg)->rtindex; + else + elog(ERROR, "unrecognized node type in jointree: %d", + (int) nodeTag(j->larg)); + if (IsA(j->rarg, RangeTblRef)) + colinfo->rightrti = ((RangeTblRef *) j->rarg)->rtindex; + else if (IsA(j->rarg, JoinExpr)) + colinfo->rightrti = ((JoinExpr *) j->rarg)->rtindex; + else + elog(ERROR, "unrecognized node type in jointree: %d", + (int) nodeTag(j->rarg)); + + /* Assert children will be processed earlier than join in second pass */ + Assert(colinfo->leftrti < j->rtindex); + Assert(colinfo->rightrti < j->rtindex); + + /* Initialize result arrays with zeroes */ + numjoincols = list_length(jrte->joinaliasvars); + Assert(numjoincols == list_length(jrte->eref->colnames)); + colinfo->leftattnos = (int *) palloc0(numjoincols * sizeof(int)); + colinfo->rightattnos = (int *) palloc0(numjoincols * sizeof(int)); + + /* + * Deconstruct RTE's joinleftcols/joinrightcols into desired format. + * Recall that the column(s) merged due to USING are the first column(s) + * of the join output. We need not do anything special while scanning + * joinleftcols, but while scanning joinrightcols we must distinguish + * merged from unmerged columns. + */ + jcolno = 0; + foreach(lc, jrte->joinleftcols) + { + int leftattno = lfirst_int(lc); + + colinfo->leftattnos[jcolno++] = leftattno; + } + rcolno = 0; + foreach(lc, jrte->joinrightcols) + { + int rightattno = lfirst_int(lc); + + if (rcolno < jrte->joinmergedcols) /* merged column? */ + colinfo->rightattnos[rcolno] = rightattno; + else + colinfo->rightattnos[jcolno++] = rightattno; + rcolno++; + } + Assert(jcolno == numjoincols); +} + +/* + * get_rtable_name: convenience function to get a previously assigned RTE alias + * + * The RTE must belong to the topmost namespace level in "context". + */ +static char * +get_rtable_name(int rtindex, deparse_context *context) +{ + deparse_namespace *dpns = (deparse_namespace *) linitial(context->namespaces); + + Assert(rtindex > 0 && rtindex <= list_length(dpns->rtable_names)); + return (char *) list_nth(dpns->rtable_names, rtindex - 1); +} + +/* + * set_deparse_plan: set up deparse_namespace to parse subexpressions + * of a given Plan node + * + * This sets the plan, outer_plan, inner_plan, outer_tlist, inner_tlist, + * and index_tlist fields. Caller must already have adjusted the ancestors + * list if necessary. Note that the rtable, subplans, and ctes fields do + * not need to change when shifting attention to different plan nodes in a + * single plan tree. + */ +static void +set_deparse_plan(deparse_namespace *dpns, Plan *plan) +{ + dpns->plan = plan; + + /* + * We special-case Append and MergeAppend to pretend that the first child + * plan is the OUTER referent; we have to interpret OUTER Vars in their + * tlists according to one of the children, and the first one is the most + * natural choice. + */ + if (IsA(plan, Append)) + dpns->outer_plan = linitial(((Append *) plan)->appendplans); + else if (IsA(plan, MergeAppend)) + dpns->outer_plan = linitial(((MergeAppend *) plan)->mergeplans); + else + dpns->outer_plan = outerPlan(plan); + + if (dpns->outer_plan) + dpns->outer_tlist = dpns->outer_plan->targetlist; + else + dpns->outer_tlist = NIL; + + /* + * For a SubqueryScan, pretend the subplan is INNER referent. (We don't + * use OUTER because that could someday conflict with the normal meaning.) + * Likewise, for a CteScan, pretend the subquery's plan is INNER referent. + * For a WorkTableScan, locate the parent RecursiveUnion plan node and use + * that as INNER referent. + * + * For ON CONFLICT .. UPDATE we just need the inner tlist to point to the + * excluded expression's tlist. (Similar to the SubqueryScan we don't want + * to reuse OUTER, it's used for RETURNING in some modify table cases, + * although not INSERT .. CONFLICT). + */ + if (IsA(plan, SubqueryScan)) + dpns->inner_plan = ((SubqueryScan *) plan)->subplan; + else if (IsA(plan, CteScan)) + dpns->inner_plan = list_nth(dpns->subplans, + ((CteScan *) plan)->ctePlanId - 1); + else if (IsA(plan, WorkTableScan)) + dpns->inner_plan = find_recursive_union(dpns, + (WorkTableScan *) plan); + else if (IsA(plan, ModifyTable)) + dpns->inner_plan = plan; + else + dpns->inner_plan = innerPlan(plan); + + if (IsA(plan, ModifyTable)) + dpns->inner_tlist = ((ModifyTable *) plan)->exclRelTlist; + else if (dpns->inner_plan) + dpns->inner_tlist = dpns->inner_plan->targetlist; + else + dpns->inner_tlist = NIL; + + /* Set up referent for INDEX_VAR Vars, if needed */ + if (IsA(plan, IndexOnlyScan)) + dpns->index_tlist = ((IndexOnlyScan *) plan)->indextlist; + else if (IsA(plan, ForeignScan)) + dpns->index_tlist = ((ForeignScan *) plan)->fdw_scan_tlist; + else if (IsA(plan, CustomScan)) + dpns->index_tlist = ((CustomScan *) plan)->custom_scan_tlist; + else + dpns->index_tlist = NIL; +} + +/* + * Locate the ancestor plan node that is the RecursiveUnion generating + * the WorkTableScan's work table. We can match on wtParam, since that + * should be unique within the plan tree. + */ +static Plan * +find_recursive_union(deparse_namespace *dpns, WorkTableScan *wtscan) +{ + ListCell *lc; + + foreach(lc, dpns->ancestors) + { + Plan *ancestor = (Plan *) lfirst(lc); + + if (IsA(ancestor, RecursiveUnion) && + ((RecursiveUnion *) ancestor)->wtParam == wtscan->wtParam) + return ancestor; + } + elog(ERROR, "could not find RecursiveUnion for WorkTableScan with wtParam %d", + wtscan->wtParam); + return NULL; +} + +/* + * push_child_plan: temporarily transfer deparsing attention to a child plan + * + * When expanding an OUTER_VAR or INNER_VAR reference, we must adjust the + * deparse context in case the referenced expression itself uses + * OUTER_VAR/INNER_VAR. We modify the top stack entry in-place to avoid + * affecting levelsup issues (although in a Plan tree there really shouldn't + * be any). + * + * Caller must provide a local deparse_namespace variable to save the + * previous state for pop_child_plan. + */ +static void +push_child_plan(deparse_namespace *dpns, Plan *plan, + deparse_namespace *save_dpns) +{ + /* Save state for restoration later */ + *save_dpns = *dpns; + + /* Link current plan node into ancestors list */ + dpns->ancestors = lcons(dpns->plan, dpns->ancestors); + + /* Set attention on selected child */ + set_deparse_plan(dpns, plan); +} + +/* + * pop_child_plan: undo the effects of push_child_plan + */ +static void +pop_child_plan(deparse_namespace *dpns, deparse_namespace *save_dpns) +{ + List *ancestors; + + /* Get rid of ancestors list cell added by push_child_plan */ + ancestors = list_delete_first(dpns->ancestors); + + /* Restore fields changed by push_child_plan */ + *dpns = *save_dpns; + + /* Make sure dpns->ancestors is right (may be unnecessary) */ + dpns->ancestors = ancestors; +} + +/* + * push_ancestor_plan: temporarily transfer deparsing attention to an + * ancestor plan + * + * When expanding a Param reference, we must adjust the deparse context + * to match the plan node that contains the expression being printed; + * otherwise we'd fail if that expression itself contains a Param or + * OUTER_VAR/INNER_VAR/INDEX_VAR variable. + * + * The target ancestor is conveniently identified by the ListCell holding it + * in dpns->ancestors. + * + * Caller must provide a local deparse_namespace variable to save the + * previous state for pop_ancestor_plan. + */ +static void +push_ancestor_plan(deparse_namespace *dpns, ListCell *ancestor_cell, + deparse_namespace *save_dpns) +{ + Plan *plan = (Plan *) lfirst(ancestor_cell); + + /* Save state for restoration later */ + *save_dpns = *dpns; + + /* Build a new ancestor list with just this node's ancestors */ + dpns->ancestors = + list_copy_tail(dpns->ancestors, + list_cell_number(dpns->ancestors, ancestor_cell) + 1); + + /* Set attention on selected ancestor */ + set_deparse_plan(dpns, plan); +} + +/* + * pop_ancestor_plan: undo the effects of push_ancestor_plan + */ +static void +pop_ancestor_plan(deparse_namespace *dpns, deparse_namespace *save_dpns) +{ + /* Free the ancestor list made in push_ancestor_plan */ + list_free(dpns->ancestors); + + /* Restore fields changed by push_ancestor_plan */ + *dpns = *save_dpns; +} + + +/* ---------- + * make_ruledef - reconstruct the CREATE RULE command + * for a given pg_rewrite tuple + * ---------- + */ +static void +make_ruledef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc, + int prettyFlags) +{ + char *rulename; + char ev_type; + Oid ev_class; + bool is_instead; + char *ev_qual; + char *ev_action; + List *actions; + Relation ev_relation; + TupleDesc viewResultDesc = NULL; + int fno; + Datum dat; + bool isnull; + + /* + * Get the attribute values from the rules tuple + */ + fno = SPI_fnumber(rulettc, "rulename"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + rulename = NameStr(*(DatumGetName(dat))); + + fno = SPI_fnumber(rulettc, "ev_type"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + ev_type = DatumGetChar(dat); + + fno = SPI_fnumber(rulettc, "ev_class"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + ev_class = DatumGetObjectId(dat); + + fno = SPI_fnumber(rulettc, "is_instead"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + is_instead = DatumGetBool(dat); + + fno = SPI_fnumber(rulettc, "ev_qual"); + ev_qual = SPI_getvalue(ruletup, rulettc, fno); + Assert(ev_qual != NULL); + + fno = SPI_fnumber(rulettc, "ev_action"); + ev_action = SPI_getvalue(ruletup, rulettc, fno); + Assert(ev_action != NULL); + actions = (List *) stringToNode(ev_action); + if (actions == NIL) + elog(ERROR, "invalid empty ev_action list"); + + ev_relation = table_open(ev_class, AccessShareLock); + + /* + * Build the rules definition text + */ + appendStringInfo(buf, "CREATE RULE %s AS", + quote_identifier(rulename)); + + if (prettyFlags & PRETTYFLAG_INDENT) + appendStringInfoString(buf, "\n ON "); + else + appendStringInfoString(buf, " ON "); + + /* The event the rule is fired for */ + switch (ev_type) + { + case '1': + appendStringInfoString(buf, "SELECT"); + viewResultDesc = RelationGetDescr(ev_relation); + break; + + case '2': + appendStringInfoString(buf, "UPDATE"); + break; + + case '3': + appendStringInfoString(buf, "INSERT"); + break; + + case '4': + appendStringInfoString(buf, "DELETE"); + break; + + default: + ereport(ERROR, + (errcode(ERRCODE_FEATURE_NOT_SUPPORTED), + errmsg("rule \"%s\" has unsupported event type %d", + rulename, ev_type))); + break; + } + + /* The relation the rule is fired on */ + appendStringInfo(buf, " TO %s", + (prettyFlags & PRETTYFLAG_SCHEMA) ? + generate_relation_name(ev_class, NIL) : + generate_qualified_relation_name(ev_class)); + + /* If the rule has an event qualification, add it */ + if (strcmp(ev_qual, "<>") != 0) + { + Node *qual; + Query *query; + deparse_context context; + deparse_namespace dpns; + + if (prettyFlags & PRETTYFLAG_INDENT) + appendStringInfoString(buf, "\n "); + appendStringInfoString(buf, " WHERE "); + + qual = stringToNode(ev_qual); + + /* + * We need to make a context for recognizing any Vars in the qual + * (which can only be references to OLD and NEW). Use the rtable of + * the first query in the action list for this purpose. + */ + query = (Query *) linitial(actions); + + /* + * If the action is INSERT...SELECT, OLD/NEW have been pushed down + * into the SELECT, and that's what we need to look at. (Ugly kluge + * ... try to fix this when we redesign querytrees.) + */ + query = getInsertSelectQuery(query, NULL); + + /* Must acquire locks right away; see notes in get_query_def() */ + AcquireRewriteLocks(query, false, false); + + context.buf = buf; + context.namespaces = list_make1(&dpns); + context.windowClause = NIL; + context.windowTList = NIL; + context.varprefix = (list_length(query->rtable) != 1); + context.prettyFlags = prettyFlags; + context.wrapColumn = WRAP_COLUMN_DEFAULT; + context.indentLevel = PRETTYINDENT_STD; + context.special_exprkind = EXPR_KIND_NONE; + context.appendparents = NULL; + + set_deparse_for_query(&dpns, query, NIL); + + get_rule_expr(qual, &context, false); + } + + appendStringInfoString(buf, " DO "); + + /* The INSTEAD keyword (if so) */ + if (is_instead) + appendStringInfoString(buf, "INSTEAD "); + + /* Finally the rules actions */ + if (list_length(actions) > 1) + { + ListCell *action; + Query *query; + + appendStringInfoChar(buf, '('); + foreach(action, actions) + { + query = (Query *) lfirst(action); + get_query_def(query, buf, NIL, viewResultDesc, true, + prettyFlags, WRAP_COLUMN_DEFAULT, 0); + if (prettyFlags) + appendStringInfoString(buf, ";\n"); + else + appendStringInfoString(buf, "; "); + } + appendStringInfoString(buf, ");"); + } + else + { + Query *query; + + query = (Query *) linitial(actions); + get_query_def(query, buf, NIL, viewResultDesc, true, + prettyFlags, WRAP_COLUMN_DEFAULT, 0); + appendStringInfoChar(buf, ';'); + } + + table_close(ev_relation, AccessShareLock); +} + + +/* ---------- + * make_viewdef - reconstruct the SELECT part of a + * view rewrite rule + * ---------- + */ +static void +make_viewdef(StringInfo buf, HeapTuple ruletup, TupleDesc rulettc, + int prettyFlags, int wrapColumn) +{ + Query *query; + char ev_type; + Oid ev_class; + bool is_instead; + char *ev_qual; + char *ev_action; + List *actions; + Relation ev_relation; + int fno; + Datum dat; + bool isnull; + + /* + * Get the attribute values from the rules tuple + */ + fno = SPI_fnumber(rulettc, "ev_type"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + ev_type = DatumGetChar(dat); + + fno = SPI_fnumber(rulettc, "ev_class"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + ev_class = DatumGetObjectId(dat); + + fno = SPI_fnumber(rulettc, "is_instead"); + dat = SPI_getbinval(ruletup, rulettc, fno, &isnull); + Assert(!isnull); + is_instead = DatumGetBool(dat); + + fno = SPI_fnumber(rulettc, "ev_qual"); + ev_qual = SPI_getvalue(ruletup, rulettc, fno); + Assert(ev_qual != NULL); + + fno = SPI_fnumber(rulettc, "ev_action"); + ev_action = SPI_getvalue(ruletup, rulettc, fno); + Assert(ev_action != NULL); + actions = (List *) stringToNode(ev_action); + + if (list_length(actions) != 1) + { + /* keep output buffer empty and leave */ + return; + } + + query = (Query *) linitial(actions); + + if (ev_type != '1' || !is_instead || + strcmp(ev_qual, "<>") != 0 || query->commandType != CMD_SELECT) + { + /* keep output buffer empty and leave */ + return; + } + + ev_relation = table_open(ev_class, AccessShareLock); + + get_query_def(query, buf, NIL, RelationGetDescr(ev_relation), true, + prettyFlags, wrapColumn, 0); + appendStringInfoChar(buf, ';'); + + table_close(ev_relation, AccessShareLock); +} + + +/* ---------- + * get_query_def - Parse back one query parsetree + * + * query: parsetree to be displayed + * buf: output text is appended to buf + * parentnamespace: list (initially empty) of outer-level deparse_namespace's + * resultDesc: if not NULL, the output tuple descriptor for the view + * represented by a SELECT query. We use the column names from it + * to label SELECT output columns, in preference to names in the query + * colNamesVisible: true if the surrounding context cares about the output + * column names at all (as, for example, an EXISTS() context does not); + * when false, we can suppress dummy column labels such as "?column?" + * prettyFlags: bitmask of PRETTYFLAG_XXX options + * wrapColumn: maximum line length, or -1 to disable wrapping + * startIndent: initial indentation amount + * ---------- + */ +static void +get_query_def(Query *query, StringInfo buf, List *parentnamespace, + TupleDesc resultDesc, bool colNamesVisible, + int prettyFlags, int wrapColumn, int startIndent) +{ + deparse_context context; + deparse_namespace dpns; + + /* Guard against excessively long or deeply-nested queries */ + CHECK_FOR_INTERRUPTS(); + check_stack_depth(); + + /* + * Before we begin to examine the query, acquire locks on referenced + * relations, and fix up deleted columns in JOIN RTEs. This ensures + * consistent results. Note we assume it's OK to scribble on the passed + * querytree! + * + * We are only deparsing the query (we are not about to execute it), so we + * only need AccessShareLock on the relations it mentions. + */ + AcquireRewriteLocks(query, false, false); + + context.buf = buf; + context.namespaces = lcons(&dpns, list_copy(parentnamespace)); + context.windowClause = NIL; + context.windowTList = NIL; + context.varprefix = (parentnamespace != NIL || + list_length(query->rtable) != 1); + context.prettyFlags = prettyFlags; + context.wrapColumn = wrapColumn; + context.indentLevel = startIndent; + context.special_exprkind = EXPR_KIND_NONE; + context.appendparents = NULL; + + set_deparse_for_query(&dpns, query, parentnamespace); + + switch (query->commandType) + { + case CMD_SELECT: + get_select_query_def(query, &context, resultDesc, colNamesVisible); + break; + + case CMD_UPDATE: + get_update_query_def(query, &context, colNamesVisible); + break; + + case CMD_INSERT: + get_insert_query_def(query, &context, colNamesVisible); + break; + + case CMD_DELETE: + get_delete_query_def(query, &context, colNamesVisible); + break; + + case CMD_NOTHING: + appendStringInfoString(buf, "NOTHING"); + break; + + case CMD_UTILITY: + get_utility_query_def(query, &context); + break; + + default: + elog(ERROR, "unrecognized query command type: %d", + query->commandType); + break; + } +} + +/* ---------- + * get_values_def - Parse back a VALUES list + * ---------- + */ +static void +get_values_def(List *values_lists, deparse_context *context) +{ + StringInfo buf = context->buf; + bool first_list = true; + ListCell *vtl; + + appendStringInfoString(buf, "VALUES "); + + foreach(vtl, values_lists) + { + List *sublist = (List *) lfirst(vtl); + bool first_col = true; + ListCell *lc; + + if (first_list) + first_list = false; + else + appendStringInfoString(buf, ", "); + + appendStringInfoChar(buf, '('); + foreach(lc, sublist) + { + Node *col = (Node *) lfirst(lc); + + if (first_col) + first_col = false; + else + appendStringInfoChar(buf, ','); + + /* + * Print the value. Whole-row Vars need special treatment. + */ + get_rule_expr_toplevel(col, context, false); + } + appendStringInfoChar(buf, ')'); + } +} + +/* ---------- + * get_with_clause - Parse back a WITH clause + * ---------- + */ +static void +get_with_clause(Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + const char *sep; + ListCell *l; + + if (query->cteList == NIL) + return; + + if (PRETTY_INDENT(context)) + { + context->indentLevel += PRETTYINDENT_STD; + appendStringInfoChar(buf, ' '); + } + + if (query->hasRecursive) + sep = "WITH RECURSIVE "; + else + sep = "WITH "; + foreach(l, query->cteList) + { + CommonTableExpr *cte = (CommonTableExpr *) lfirst(l); + + appendStringInfoString(buf, sep); + appendStringInfoString(buf, quote_identifier(cte->ctename)); + if (cte->aliascolnames) + { + bool first = true; + ListCell *col; + + appendStringInfoChar(buf, '('); + foreach(col, cte->aliascolnames) + { + if (first) + first = false; + else + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, + quote_identifier(strVal(lfirst(col)))); + } + appendStringInfoChar(buf, ')'); + } + appendStringInfoString(buf, " AS "); + switch (cte->ctematerialized) + { + case CTEMaterializeDefault: + break; + case CTEMaterializeAlways: + appendStringInfoString(buf, "MATERIALIZED "); + break; + case CTEMaterializeNever: + appendStringInfoString(buf, "NOT MATERIALIZED "); + break; + } + appendStringInfoChar(buf, '('); + if (PRETTY_INDENT(context)) + appendContextKeyword(context, "", 0, 0, 0); + get_query_def((Query *) cte->ctequery, buf, context->namespaces, NULL, + true, + context->prettyFlags, context->wrapColumn, + context->indentLevel); + if (PRETTY_INDENT(context)) + appendContextKeyword(context, "", 0, 0, 0); + appendStringInfoChar(buf, ')'); + + if (cte->search_clause) + { + bool first = true; + ListCell *lc; + + appendStringInfo(buf, " SEARCH %s FIRST BY ", + cte->search_clause->search_breadth_first ? "BREADTH" : "DEPTH"); + + foreach(lc, cte->search_clause->search_col_list) + { + if (first) + first = false; + else + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, + quote_identifier(strVal(lfirst(lc)))); + } + + appendStringInfo(buf, " SET %s", quote_identifier(cte->search_clause->search_seq_column)); + } + + if (cte->cycle_clause) + { + bool first = true; + ListCell *lc; + + appendStringInfoString(buf, " CYCLE "); + + foreach(lc, cte->cycle_clause->cycle_col_list) + { + if (first) + first = false; + else + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, + quote_identifier(strVal(lfirst(lc)))); + } + + appendStringInfo(buf, " SET %s", quote_identifier(cte->cycle_clause->cycle_mark_column)); + + { + Const *cmv = castNode(Const, cte->cycle_clause->cycle_mark_value); + Const *cmd = castNode(Const, cte->cycle_clause->cycle_mark_default); + + if (!(cmv->consttype == BOOLOID && !cmv->constisnull && DatumGetBool(cmv->constvalue) == true && + cmd->consttype == BOOLOID && !cmd->constisnull && DatumGetBool(cmd->constvalue) == false)) + { + appendStringInfoString(buf, " TO "); + get_rule_expr(cte->cycle_clause->cycle_mark_value, context, false); + appendStringInfoString(buf, " DEFAULT "); + get_rule_expr(cte->cycle_clause->cycle_mark_default, context, false); + } + } + + appendStringInfo(buf, " USING %s", quote_identifier(cte->cycle_clause->cycle_path_column)); + } + + sep = ", "; + } + + if (PRETTY_INDENT(context)) + { + context->indentLevel -= PRETTYINDENT_STD; + appendContextKeyword(context, "", 0, 0, 0); + } + else + appendStringInfoChar(buf, ' '); +} + +/* ---------- + * get_select_query_def - Parse back a SELECT parsetree + * ---------- + */ +static void +get_select_query_def(Query *query, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible) +{ + StringInfo buf = context->buf; + List *save_windowclause; + List *save_windowtlist; + bool force_colno; + ListCell *l; + + /* Insert the WITH clause if given */ + get_with_clause(query, context); + + /* Set up context for possible window functions */ + save_windowclause = context->windowClause; + context->windowClause = query->windowClause; + save_windowtlist = context->windowTList; + context->windowTList = query->targetList; + + /* + * If the Query node has a setOperations tree, then it's the top level of + * a UNION/INTERSECT/EXCEPT query; only the WITH, ORDER BY and LIMIT + * fields are interesting in the top query itself. + */ + if (query->setOperations) + { + get_setop_query(query->setOperations, query, context, resultDesc, + colNamesVisible); + /* ORDER BY clauses must be simple in this case */ + force_colno = true; + } + else + { + get_basic_select_query(query, context, resultDesc, colNamesVisible); + force_colno = false; + } + + /* Add the ORDER BY clause if given */ + if (query->sortClause != NIL) + { + appendContextKeyword(context, " ORDER BY ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_orderby(query->sortClause, query->targetList, + force_colno, context); + } + + /* + * Add the LIMIT/OFFSET clauses if given. If non-default options, use the + * standard spelling of LIMIT. + */ + if (query->limitOffset != NULL) + { + appendContextKeyword(context, " OFFSET ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + get_rule_expr(query->limitOffset, context, false); + } + if (query->limitCount != NULL) + { + if (query->limitOption == LIMIT_OPTION_WITH_TIES) + { + appendContextKeyword(context, " FETCH FIRST ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + get_rule_expr(query->limitCount, context, false); + appendStringInfoString(buf, " ROWS WITH TIES"); + } + else + { + appendContextKeyword(context, " LIMIT ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + if (IsA(query->limitCount, Const) && + ((Const *) query->limitCount)->constisnull) + appendStringInfoString(buf, "ALL"); + else + get_rule_expr(query->limitCount, context, false); + } + } + + /* Add FOR [KEY] UPDATE/SHARE clauses if present */ + if (query->hasForUpdate) + { + foreach(l, query->rowMarks) + { + RowMarkClause *rc = (RowMarkClause *) lfirst(l); + + /* don't print implicit clauses */ + if (rc->pushedDown) + continue; + + switch (rc->strength) + { + case LCS_NONE: + /* we intentionally throw an error for LCS_NONE */ + elog(ERROR, "unrecognized LockClauseStrength %d", + (int) rc->strength); + break; + case LCS_FORKEYSHARE: + appendContextKeyword(context, " FOR KEY SHARE", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + break; + case LCS_FORSHARE: + appendContextKeyword(context, " FOR SHARE", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + break; + case LCS_FORNOKEYUPDATE: + appendContextKeyword(context, " FOR NO KEY UPDATE", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + break; + case LCS_FORUPDATE: + appendContextKeyword(context, " FOR UPDATE", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + break; + } + + appendStringInfo(buf, " OF %s", + quote_identifier(get_rtable_name(rc->rti, + context))); + if (rc->waitPolicy == LockWaitError) + appendStringInfoString(buf, " NOWAIT"); + else if (rc->waitPolicy == LockWaitSkip) + appendStringInfoString(buf, " SKIP LOCKED"); + } + } + + context->windowClause = save_windowclause; + context->windowTList = save_windowtlist; +} + +/* + * Detect whether query looks like SELECT ... FROM VALUES(), + * with no need to rename the output columns of the VALUES RTE. + * If so, return the VALUES RTE. Otherwise return NULL. + */ +static RangeTblEntry * +get_simple_values_rte(Query *query, TupleDesc resultDesc) +{ + RangeTblEntry *result = NULL; + ListCell *lc; + + /* + * We want to detect a match even if the Query also contains OLD or NEW + * rule RTEs. So the idea is to scan the rtable and see if there is only + * one inFromCl RTE that is a VALUES RTE. + */ + foreach(lc, query->rtable) + { + RangeTblEntry *rte = (RangeTblEntry *) lfirst(lc); + + if (rte->rtekind == RTE_VALUES && rte->inFromCl) + { + if (result) + return NULL; /* multiple VALUES (probably not possible) */ + result = rte; + } + else if (rte->rtekind == RTE_RELATION && !rte->inFromCl) + continue; /* ignore rule entries */ + else + return NULL; /* something else -> not simple VALUES */ + } + + /* + * We don't need to check the targetlist in any great detail, because + * parser/analyze.c will never generate a "bare" VALUES RTE --- they only + * appear inside auto-generated sub-queries with very restricted + * structure. However, DefineView might have modified the tlist by + * injecting new column aliases, or we might have some other column + * aliases forced by a resultDesc. We can only simplify if the RTE's + * column names match the names that get_target_list() would select. + */ + if (result) + { + ListCell *lcn; + int colno; + + if (list_length(query->targetList) != list_length(result->eref->colnames)) + return NULL; /* this probably cannot happen */ + colno = 0; + forboth(lc, query->targetList, lcn, result->eref->colnames) + { + TargetEntry *tle = (TargetEntry *) lfirst(lc); + char *cname = strVal(lfirst(lcn)); + char *colname; + + if (tle->resjunk) + return NULL; /* this probably cannot happen */ + + /* compute name that get_target_list would use for column */ + colno++; + if (resultDesc && colno <= resultDesc->natts) + colname = NameStr(TupleDescAttr(resultDesc, colno - 1)->attname); + else + colname = tle->resname; + + /* does it match the VALUES RTE? */ + if (colname == NULL || strcmp(colname, cname) != 0) + return NULL; /* column name has been changed */ + } + } + + return result; +} + +static void +get_basic_select_query(Query *query, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible) +{ + StringInfo buf = context->buf; + RangeTblEntry *values_rte; + char *sep; + ListCell *l; + + if (PRETTY_INDENT(context)) + { + context->indentLevel += PRETTYINDENT_STD; + appendStringInfoChar(buf, ' '); + } + + /* + * If the query looks like SELECT * FROM (VALUES ...), then print just the + * VALUES part. This reverses what transformValuesClause() did at parse + * time. + */ + values_rte = get_simple_values_rte(query, resultDesc); + if (values_rte) + { + get_values_def(values_rte->values_lists, context); + return; + } + + /* + * Build up the query string - first we say SELECT + */ + if (query->isReturn) + appendStringInfoString(buf, "RETURN"); + else + appendStringInfoString(buf, "SELECT"); + + /* Add the DISTINCT clause if given */ + if (query->distinctClause != NIL) + { + if (query->hasDistinctOn) + { + appendStringInfoString(buf, " DISTINCT ON ("); + sep = ""; + foreach(l, query->distinctClause) + { + SortGroupClause *srt = (SortGroupClause *) lfirst(l); + + appendStringInfoString(buf, sep); + get_rule_sortgroupclause(srt->tleSortGroupRef, query->targetList, + false, context); + sep = ", "; + } + appendStringInfoChar(buf, ')'); + } + else + appendStringInfoString(buf, " DISTINCT"); + } + + /* Then we tell what to select (the targetlist) */ + get_target_list(query->targetList, context, resultDesc, colNamesVisible); + + /* Add the FROM clause if needed */ + get_from_clause(query, " FROM ", context); + + /* Add the WHERE clause if given */ + if (query->jointree->quals != NULL) + { + appendContextKeyword(context, " WHERE ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_expr(query->jointree->quals, context, false); + } + + /* Add the GROUP BY clause if given */ + if (query->groupClause != NULL || query->groupingSets != NULL) + { + ParseExprKind save_exprkind; + + appendContextKeyword(context, " GROUP BY ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + if (query->groupDistinct) + appendStringInfoString(buf, "DISTINCT "); + + save_exprkind = context->special_exprkind; + context->special_exprkind = EXPR_KIND_GROUP_BY; + + if (query->groupingSets == NIL) + { + sep = ""; + foreach(l, query->groupClause) + { + SortGroupClause *grp = (SortGroupClause *) lfirst(l); + + appendStringInfoString(buf, sep); + get_rule_sortgroupclause(grp->tleSortGroupRef, query->targetList, + false, context); + sep = ", "; + } + } + else + { + sep = ""; + foreach(l, query->groupingSets) + { + GroupingSet *grp = lfirst(l); + + appendStringInfoString(buf, sep); + get_rule_groupingset(grp, query->targetList, true, context); + sep = ", "; + } + } + + context->special_exprkind = save_exprkind; + } + + /* Add the HAVING clause if given */ + if (query->havingQual != NULL) + { + appendContextKeyword(context, " HAVING ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 0); + get_rule_expr(query->havingQual, context, false); + } + + /* Add the WINDOW clause if needed */ + if (query->windowClause != NIL) + get_rule_windowclause(query, context); +} + +/* ---------- + * get_target_list - Parse back a SELECT target list + * + * This is also used for RETURNING lists in INSERT/UPDATE/DELETE. + * + * resultDesc and colNamesVisible are as for get_query_def() + * ---------- + */ +static void +get_target_list(List *targetList, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible) +{ + StringInfo buf = context->buf; + StringInfoData targetbuf; + bool last_was_multiline = false; + char *sep; + int colno; + ListCell *l; + + /* we use targetbuf to hold each TLE's text temporarily */ + initStringInfo(&targetbuf); + + sep = " "; + colno = 0; + foreach(l, targetList) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + char *colname; + char *attname; + + if (tle->resjunk) + continue; /* ignore junk entries */ + + appendStringInfoString(buf, sep); + sep = ", "; + colno++; + + /* + * Put the new field text into targetbuf so we can decide after we've + * got it whether or not it needs to go on a new line. + */ + resetStringInfo(&targetbuf); + context->buf = &targetbuf; + + /* + * We special-case Var nodes rather than using get_rule_expr. This is + * needed because get_rule_expr will display a whole-row Var as + * "foo.*", which is the preferred notation in most contexts, but at + * the top level of a SELECT list it's not right (the parser will + * expand that notation into multiple columns, yielding behavior + * different from a whole-row Var). We need to call get_variable + * directly so that we can tell it to do the right thing, and so that + * we can get the attribute name which is the default AS label. + */ + if (tle->expr && (IsA(tle->expr, Var))) + { + attname = get_variable((Var *) tle->expr, 0, true, context); + } + else + { + get_rule_expr((Node *) tle->expr, context, true); + + /* + * When colNamesVisible is true, we should always show the + * assigned column name explicitly. Otherwise, show it only if + * it's not FigureColname's fallback. + */ + attname = colNamesVisible ? NULL : "?column?"; + } + + /* + * Figure out what the result column should be called. In the context + * of a view, use the view's tuple descriptor (so as to pick up the + * effects of any column RENAME that's been done on the view). + * Otherwise, just use what we can find in the TLE. + */ + if (resultDesc && colno <= resultDesc->natts) + colname = NameStr(TupleDescAttr(resultDesc, colno - 1)->attname); + else + colname = tle->resname; + + /* Show AS unless the column's name is correct as-is */ + if (colname) /* resname could be NULL */ + { + if (attname == NULL || strcmp(attname, colname) != 0) + appendStringInfo(&targetbuf, " AS %s", quote_identifier(colname)); + } + + /* Restore context's output buffer */ + context->buf = buf; + + /* Consider line-wrapping if enabled */ + if (PRETTY_INDENT(context) && context->wrapColumn >= 0) + { + int leading_nl_pos; + + /* Does the new field start with a new line? */ + if (targetbuf.len > 0 && targetbuf.data[0] == '\n') + leading_nl_pos = 0; + else + leading_nl_pos = -1; + + /* If so, we shouldn't add anything */ + if (leading_nl_pos >= 0) + { + /* instead, remove any trailing spaces currently in buf */ + removeStringInfoSpaces(buf); + } + else + { + char *trailing_nl; + + /* Locate the start of the current line in the output buffer */ + trailing_nl = strrchr(buf->data, '\n'); + if (trailing_nl == NULL) + trailing_nl = buf->data; + else + trailing_nl++; + + /* + * Add a newline, plus some indentation, if the new field is + * not the first and either the new field would cause an + * overflow or the last field used more than one line. + */ + if (colno > 1 && + ((strlen(trailing_nl) + targetbuf.len > context->wrapColumn) || + last_was_multiline)) + appendContextKeyword(context, "", -PRETTYINDENT_STD, + PRETTYINDENT_STD, PRETTYINDENT_VAR); + } + + /* Remember this field's multiline status for next iteration */ + last_was_multiline = + (strchr(targetbuf.data + leading_nl_pos + 1, '\n') != NULL); + } + + /* Add the new field */ + appendBinaryStringInfo(buf, targetbuf.data, targetbuf.len); + } + + /* clean up */ + pfree(targetbuf.data); +} + +static void +get_setop_query(Node *setOp, Query *query, deparse_context *context, + TupleDesc resultDesc, bool colNamesVisible) +{ + StringInfo buf = context->buf; + bool need_paren; + + /* Guard against excessively long or deeply-nested queries */ + CHECK_FOR_INTERRUPTS(); + check_stack_depth(); + + if (IsA(setOp, RangeTblRef)) + { + RangeTblRef *rtr = (RangeTblRef *) setOp; + RangeTblEntry *rte = rt_fetch(rtr->rtindex, query->rtable); + Query *subquery = rte->subquery; + + Assert(subquery != NULL); + Assert(subquery->setOperations == NULL); + /* Need parens if WITH, ORDER BY, FOR UPDATE, or LIMIT; see gram.y */ + need_paren = (subquery->cteList || + subquery->sortClause || + subquery->rowMarks || + subquery->limitOffset || + subquery->limitCount); + if (need_paren) + appendStringInfoChar(buf, '('); + get_query_def(subquery, buf, context->namespaces, resultDesc, + colNamesVisible, + context->prettyFlags, context->wrapColumn, + context->indentLevel); + if (need_paren) + appendStringInfoChar(buf, ')'); + } + else if (IsA(setOp, SetOperationStmt)) + { + SetOperationStmt *op = (SetOperationStmt *) setOp; + int subindent; + + /* + * We force parens when nesting two SetOperationStmts, except when the + * lefthand input is another setop of the same kind. Syntactically, + * we could omit parens in rather more cases, but it seems best to use + * parens to flag cases where the setop operator changes. If we use + * parens, we also increase the indentation level for the child query. + * + * There are some cases in which parens are needed around a leaf query + * too, but those are more easily handled at the next level down (see + * code above). + */ + if (IsA(op->larg, SetOperationStmt)) + { + SetOperationStmt *lop = (SetOperationStmt *) op->larg; + + if (op->op == lop->op && op->all == lop->all) + need_paren = false; + else + need_paren = true; + } + else + need_paren = false; + + if (need_paren) + { + appendStringInfoChar(buf, '('); + subindent = PRETTYINDENT_STD; + appendContextKeyword(context, "", subindent, 0, 0); + } + else + subindent = 0; + + get_setop_query(op->larg, query, context, resultDesc, colNamesVisible); + + if (need_paren) + appendContextKeyword(context, ") ", -subindent, 0, 0); + else if (PRETTY_INDENT(context)) + appendContextKeyword(context, "", -subindent, 0, 0); + else + appendStringInfoChar(buf, ' '); + + switch (op->op) + { + case SETOP_UNION: + appendStringInfoString(buf, "UNION "); + break; + case SETOP_INTERSECT: + appendStringInfoString(buf, "INTERSECT "); + break; + case SETOP_EXCEPT: + appendStringInfoString(buf, "EXCEPT "); + break; + default: + elog(ERROR, "unrecognized set op: %d", + (int) op->op); + } + if (op->all) + appendStringInfoString(buf, "ALL "); + + /* Always parenthesize if RHS is another setop */ + need_paren = IsA(op->rarg, SetOperationStmt); + + /* + * The indentation code here is deliberately a bit different from that + * for the lefthand input, because we want the line breaks in + * different places. + */ + if (need_paren) + { + appendStringInfoChar(buf, '('); + subindent = PRETTYINDENT_STD; + } + else + subindent = 0; + appendContextKeyword(context, "", subindent, 0, 0); + + get_setop_query(op->rarg, query, context, resultDesc, false); + + if (PRETTY_INDENT(context)) + context->indentLevel -= subindent; + if (need_paren) + appendContextKeyword(context, ")", 0, 0, 0); + } + else + { + elog(ERROR, "unrecognized node type: %d", + (int) nodeTag(setOp)); + } +} + +/* + * Display a sort/group clause. + * + * Also returns the expression tree, so caller need not find it again. + */ +static Node * +get_rule_sortgroupclause(Index ref, List *tlist, bool force_colno, + deparse_context *context) +{ + StringInfo buf = context->buf; + TargetEntry *tle; + Node *expr; + + tle = get_sortgroupref_tle(ref, tlist); + expr = (Node *) tle->expr; + + /* + * Use column-number form if requested by caller. Otherwise, if + * expression is a constant, force it to be dumped with an explicit cast + * as decoration --- this is because a simple integer constant is + * ambiguous (and will be misinterpreted by findTargetlistEntry()) if we + * dump it without any decoration. If it's anything more complex than a + * simple Var, then force extra parens around it, to ensure it can't be + * misinterpreted as a cube() or rollup() construct. + */ + if (force_colno) + { + Assert(!tle->resjunk); + appendStringInfo(buf, "%d", tle->resno); + } + else if (expr && IsA(expr, Const)) + get_const_expr((Const *) expr, context, 1); + else if (!expr || IsA(expr, Var)) + get_rule_expr(expr, context, true); + else + { + /* + * We must force parens for function-like expressions even if + * PRETTY_PAREN is off, since those are the ones in danger of + * misparsing. For other expressions we need to force them only if + * PRETTY_PAREN is on, since otherwise the expression will output them + * itself. (We can't skip the parens.) + */ + bool need_paren = (PRETTY_PAREN(context) + || IsA(expr, FuncExpr) + || IsA(expr, Aggref) + || IsA(expr, WindowFunc)); + + if (need_paren) + appendStringInfoChar(context->buf, '('); + get_rule_expr(expr, context, true); + if (need_paren) + appendStringInfoChar(context->buf, ')'); + } + + return expr; +} + +/* + * Display a GroupingSet + */ +static void +get_rule_groupingset(GroupingSet *gset, List *targetlist, + bool omit_parens, deparse_context *context) +{ + ListCell *l; + StringInfo buf = context->buf; + bool omit_child_parens = true; + char *sep = ""; + + switch (gset->kind) + { + case GROUPING_SET_EMPTY: + appendStringInfoString(buf, "()"); + return; + + case GROUPING_SET_SIMPLE: + { + if (!omit_parens || list_length(gset->content) != 1) + appendStringInfoChar(buf, '('); + + foreach(l, gset->content) + { + Index ref = lfirst_int(l); + + appendStringInfoString(buf, sep); + get_rule_sortgroupclause(ref, targetlist, + false, context); + sep = ", "; + } + + if (!omit_parens || list_length(gset->content) != 1) + appendStringInfoChar(buf, ')'); + } + return; + + case GROUPING_SET_ROLLUP: + appendStringInfoString(buf, "ROLLUP("); + break; + case GROUPING_SET_CUBE: + appendStringInfoString(buf, "CUBE("); + break; + case GROUPING_SET_SETS: + appendStringInfoString(buf, "GROUPING SETS ("); + omit_child_parens = false; + break; + } + + foreach(l, gset->content) + { + appendStringInfoString(buf, sep); + get_rule_groupingset(lfirst(l), targetlist, omit_child_parens, context); + sep = ", "; + } + + appendStringInfoChar(buf, ')'); +} + +/* + * Display an ORDER BY list. + */ +static void +get_rule_orderby(List *orderList, List *targetList, + bool force_colno, deparse_context *context) +{ + StringInfo buf = context->buf; + const char *sep; + ListCell *l; + + sep = ""; + foreach(l, orderList) + { + SortGroupClause *srt = (SortGroupClause *) lfirst(l); + Node *sortexpr; + Oid sortcoltype; + TypeCacheEntry *typentry; + + appendStringInfoString(buf, sep); + sortexpr = get_rule_sortgroupclause(srt->tleSortGroupRef, targetList, + force_colno, context); + sortcoltype = exprType(sortexpr); + /* See whether operator is default < or > for datatype */ + typentry = lookup_type_cache(sortcoltype, + TYPECACHE_LT_OPR | TYPECACHE_GT_OPR); + if (srt->sortop == typentry->lt_opr) + { + /* ASC is default, so emit nothing for it */ + if (srt->nulls_first) + appendStringInfoString(buf, " NULLS FIRST"); + } + else if (srt->sortop == typentry->gt_opr) + { + appendStringInfoString(buf, " DESC"); + /* DESC defaults to NULLS FIRST */ + if (!srt->nulls_first) + appendStringInfoString(buf, " NULLS LAST"); + } + else + { + appendStringInfo(buf, " USING %s", + generate_operator_name(srt->sortop, + sortcoltype, + sortcoltype)); + /* be specific to eliminate ambiguity */ + if (srt->nulls_first) + appendStringInfoString(buf, " NULLS FIRST"); + else + appendStringInfoString(buf, " NULLS LAST"); + } + sep = ", "; + } +} + +/* + * Display a WINDOW clause. + * + * Note that the windowClause list might contain only anonymous window + * specifications, in which case we should print nothing here. + */ +static void +get_rule_windowclause(Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + const char *sep; + ListCell *l; + + sep = NULL; + foreach(l, query->windowClause) + { + WindowClause *wc = (WindowClause *) lfirst(l); + + if (wc->name == NULL) + continue; /* ignore anonymous windows */ + + if (sep == NULL) + appendContextKeyword(context, " WINDOW ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + else + appendStringInfoString(buf, sep); + + appendStringInfo(buf, "%s AS ", quote_identifier(wc->name)); + + get_rule_windowspec(wc, query->targetList, context); + + sep = ", "; + } +} + +/* + * Display a window definition + */ +static void +get_rule_windowspec(WindowClause *wc, List *targetList, + deparse_context *context) +{ + StringInfo buf = context->buf; + bool needspace = false; + const char *sep; + ListCell *l; + + appendStringInfoChar(buf, '('); + if (wc->refname) + { + appendStringInfoString(buf, quote_identifier(wc->refname)); + needspace = true; + } + /* partition clauses are always inherited, so only print if no refname */ + if (wc->partitionClause && !wc->refname) + { + if (needspace) + appendStringInfoChar(buf, ' '); + appendStringInfoString(buf, "PARTITION BY "); + sep = ""; + foreach(l, wc->partitionClause) + { + SortGroupClause *grp = (SortGroupClause *) lfirst(l); + + appendStringInfoString(buf, sep); + get_rule_sortgroupclause(grp->tleSortGroupRef, targetList, + false, context); + sep = ", "; + } + needspace = true; + } + /* print ordering clause only if not inherited */ + if (wc->orderClause && !wc->copiedOrder) + { + if (needspace) + appendStringInfoChar(buf, ' '); + appendStringInfoString(buf, "ORDER BY "); + get_rule_orderby(wc->orderClause, targetList, false, context); + needspace = true; + } + /* framing clause is never inherited, so print unless it's default */ + if (wc->frameOptions & FRAMEOPTION_NONDEFAULT) + { + if (needspace) + appendStringInfoChar(buf, ' '); + if (wc->frameOptions & FRAMEOPTION_RANGE) + appendStringInfoString(buf, "RANGE "); + else if (wc->frameOptions & FRAMEOPTION_ROWS) + appendStringInfoString(buf, "ROWS "); + else if (wc->frameOptions & FRAMEOPTION_GROUPS) + appendStringInfoString(buf, "GROUPS "); + else + Assert(false); + if (wc->frameOptions & FRAMEOPTION_BETWEEN) + appendStringInfoString(buf, "BETWEEN "); + if (wc->frameOptions & FRAMEOPTION_START_UNBOUNDED_PRECEDING) + appendStringInfoString(buf, "UNBOUNDED PRECEDING "); + else if (wc->frameOptions & FRAMEOPTION_START_CURRENT_ROW) + appendStringInfoString(buf, "CURRENT ROW "); + else if (wc->frameOptions & FRAMEOPTION_START_OFFSET) + { + get_rule_expr(wc->startOffset, context, false); + if (wc->frameOptions & FRAMEOPTION_START_OFFSET_PRECEDING) + appendStringInfoString(buf, " PRECEDING "); + else if (wc->frameOptions & FRAMEOPTION_START_OFFSET_FOLLOWING) + appendStringInfoString(buf, " FOLLOWING "); + else + Assert(false); + } + else + Assert(false); + if (wc->frameOptions & FRAMEOPTION_BETWEEN) + { + appendStringInfoString(buf, "AND "); + if (wc->frameOptions & FRAMEOPTION_END_UNBOUNDED_FOLLOWING) + appendStringInfoString(buf, "UNBOUNDED FOLLOWING "); + else if (wc->frameOptions & FRAMEOPTION_END_CURRENT_ROW) + appendStringInfoString(buf, "CURRENT ROW "); + else if (wc->frameOptions & FRAMEOPTION_END_OFFSET) + { + get_rule_expr(wc->endOffset, context, false); + if (wc->frameOptions & FRAMEOPTION_END_OFFSET_PRECEDING) + appendStringInfoString(buf, " PRECEDING "); + else if (wc->frameOptions & FRAMEOPTION_END_OFFSET_FOLLOWING) + appendStringInfoString(buf, " FOLLOWING "); + else + Assert(false); + } + else + Assert(false); + } + if (wc->frameOptions & FRAMEOPTION_EXCLUDE_CURRENT_ROW) + appendStringInfoString(buf, "EXCLUDE CURRENT ROW "); + else if (wc->frameOptions & FRAMEOPTION_EXCLUDE_GROUP) + appendStringInfoString(buf, "EXCLUDE GROUP "); + else if (wc->frameOptions & FRAMEOPTION_EXCLUDE_TIES) + appendStringInfoString(buf, "EXCLUDE TIES "); + /* we will now have a trailing space; remove it */ + buf->len--; + } + appendStringInfoChar(buf, ')'); +} + +/* ---------- + * get_insert_query_def - Parse back an INSERT parsetree + * ---------- + */ +static void +get_insert_query_def(Query *query, deparse_context *context, + bool colNamesVisible) +{ + StringInfo buf = context->buf; + RangeTblEntry *select_rte = NULL; + RangeTblEntry *values_rte = NULL; + RangeTblEntry *rte; + char *sep; + ListCell *l; + List *strippedexprs; + + /* Insert the WITH clause if given */ + get_with_clause(query, context); + + /* + * If it's an INSERT ... SELECT or multi-row VALUES, there will be a + * single RTE for the SELECT or VALUES. Plain VALUES has neither. + */ + foreach(l, query->rtable) + { + rte = (RangeTblEntry *) lfirst(l); + + if (rte->rtekind == RTE_SUBQUERY) + { + if (select_rte) + elog(ERROR, "too many subquery RTEs in INSERT"); + select_rte = rte; + } + + if (rte->rtekind == RTE_VALUES) + { + if (values_rte) + elog(ERROR, "too many values RTEs in INSERT"); + values_rte = rte; + } + } + if (select_rte && values_rte) + elog(ERROR, "both subquery and values RTEs in INSERT"); + + /* + * Start the query with INSERT INTO relname + */ + rte = rt_fetch(query->resultRelation, query->rtable); + Assert(rte->rtekind == RTE_RELATION); + + if (PRETTY_INDENT(context)) + { + context->indentLevel += PRETTYINDENT_STD; + appendStringInfoChar(buf, ' '); + } + appendStringInfo(buf, "INSERT INTO %s ", + generate_relation_name(rte->relid, NIL)); + /* INSERT requires AS keyword for target alias */ + if (rte->alias != NULL) + appendStringInfo(buf, "AS %s ", + quote_identifier(rte->alias->aliasname)); + + /* + * Add the insert-column-names list. Any indirection decoration needed on + * the column names can be inferred from the top targetlist. + */ + strippedexprs = NIL; + sep = ""; + if (query->targetList) + appendStringInfoChar(buf, '('); + foreach(l, query->targetList) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + + if (tle->resjunk) + continue; /* ignore junk entries */ + + appendStringInfoString(buf, sep); + sep = ", "; + + /* + * Put out name of target column; look in the catalogs, not at + * tle->resname, since resname will fail to track RENAME. + */ + appendStringInfoString(buf, + quote_identifier(get_attname(rte->relid, + tle->resno, + false))); + + /* + * Print any indirection needed (subfields or subscripts), and strip + * off the top-level nodes representing the indirection assignments. + * Add the stripped expressions to strippedexprs. (If it's a + * single-VALUES statement, the stripped expressions are the VALUES to + * print below. Otherwise they're just Vars and not really + * interesting.) + */ + strippedexprs = lappend(strippedexprs, + processIndirection((Node *) tle->expr, + context)); + } + if (query->targetList) + appendStringInfoString(buf, ") "); + + if (query->override) + { + if (query->override == OVERRIDING_SYSTEM_VALUE) + appendStringInfoString(buf, "OVERRIDING SYSTEM VALUE "); + else if (query->override == OVERRIDING_USER_VALUE) + appendStringInfoString(buf, "OVERRIDING USER VALUE "); + } + + if (select_rte) + { + /* Add the SELECT */ + get_query_def(select_rte->subquery, buf, context->namespaces, NULL, + false, + context->prettyFlags, context->wrapColumn, + context->indentLevel); + } + else if (values_rte) + { + /* Add the multi-VALUES expression lists */ + get_values_def(values_rte->values_lists, context); + } + else if (strippedexprs) + { + /* Add the single-VALUES expression list */ + appendContextKeyword(context, "VALUES (", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 2); + get_rule_list_toplevel(strippedexprs, context, false); + appendStringInfoChar(buf, ')'); + } + else + { + /* No expressions, so it must be DEFAULT VALUES */ + appendStringInfoString(buf, "DEFAULT VALUES"); + } + + /* Add ON CONFLICT if present */ + if (query->onConflict) + { + OnConflictExpr *confl = query->onConflict; + + appendStringInfoString(buf, " ON CONFLICT"); + + if (confl->arbiterElems) + { + /* Add the single-VALUES expression list */ + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) confl->arbiterElems, context, false); + appendStringInfoChar(buf, ')'); + + /* Add a WHERE clause (for partial indexes) if given */ + if (confl->arbiterWhere != NULL) + { + bool save_varprefix; + + /* + * Force non-prefixing of Vars, since parser assumes that they + * belong to target relation. WHERE clause does not use + * InferenceElem, so this is separately required. + */ + save_varprefix = context->varprefix; + context->varprefix = false; + + appendContextKeyword(context, " WHERE ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_expr(confl->arbiterWhere, context, false); + + context->varprefix = save_varprefix; + } + } + else if (OidIsValid(confl->constraint)) + { + char *constraint = get_constraint_name(confl->constraint); + + if (!constraint) + elog(ERROR, "cache lookup failed for constraint %u", + confl->constraint); + appendStringInfo(buf, " ON CONSTRAINT %s", + quote_identifier(constraint)); + } + + if (confl->action == ONCONFLICT_NOTHING) + { + appendStringInfoString(buf, " DO NOTHING"); + } + else + { + appendStringInfoString(buf, " DO UPDATE SET "); + /* Deparse targetlist */ + get_update_query_targetlist_def(query, confl->onConflictSet, + context, rte); + + /* Add a WHERE clause if given */ + if (confl->onConflictWhere != NULL) + { + appendContextKeyword(context, " WHERE ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_expr(confl->onConflictWhere, context, false); + } + } + } + + /* Add RETURNING if present */ + if (query->returningList) + { + appendContextKeyword(context, " RETURNING", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_target_list(query->returningList, context, NULL, colNamesVisible); + } +} + + +/* ---------- + * get_update_query_def - Parse back an UPDATE parsetree + * ---------- + */ +static void +get_update_query_def(Query *query, deparse_context *context, + bool colNamesVisible) +{ + StringInfo buf = context->buf; + RangeTblEntry *rte; + + /* Insert the WITH clause if given */ + get_with_clause(query, context); + + /* + * Start the query with UPDATE relname SET + */ + rte = rt_fetch(query->resultRelation, query->rtable); + Assert(rte->rtekind == RTE_RELATION); + if (PRETTY_INDENT(context)) + { + appendStringInfoChar(buf, ' '); + context->indentLevel += PRETTYINDENT_STD; + } + appendStringInfo(buf, "UPDATE %s%s", + only_marker(rte), + generate_relation_name(rte->relid, NIL)); + if (rte->alias != NULL) + appendStringInfo(buf, " %s", + quote_identifier(rte->alias->aliasname)); + appendStringInfoString(buf, " SET "); + + /* Deparse targetlist */ + get_update_query_targetlist_def(query, query->targetList, context, rte); + + /* Add the FROM clause if needed */ + get_from_clause(query, " FROM ", context); + + /* Add a WHERE clause if given */ + if (query->jointree->quals != NULL) + { + appendContextKeyword(context, " WHERE ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_expr(query->jointree->quals, context, false); + } + + /* Add RETURNING if present */ + if (query->returningList) + { + appendContextKeyword(context, " RETURNING", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_target_list(query->returningList, context, NULL, colNamesVisible); + } +} + + +/* ---------- + * get_update_query_targetlist_def - Parse back an UPDATE targetlist + * ---------- + */ +static void +get_update_query_targetlist_def(Query *query, List *targetList, + deparse_context *context, RangeTblEntry *rte) +{ + StringInfo buf = context->buf; + ListCell *l; + ListCell *next_ma_cell; + int remaining_ma_columns; + const char *sep; + SubLink *cur_ma_sublink; + List *ma_sublinks; + + /* + * Prepare to deal with MULTIEXPR assignments: collect the source SubLinks + * into a list. We expect them to appear, in ID order, in resjunk tlist + * entries. + */ + ma_sublinks = NIL; + if (query->hasSubLinks) /* else there can't be any */ + { + foreach(l, targetList) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + + if (tle->resjunk && IsA(tle->expr, SubLink)) + { + SubLink *sl = (SubLink *) tle->expr; + + if (sl->subLinkType == MULTIEXPR_SUBLINK) + { + ma_sublinks = lappend(ma_sublinks, sl); + Assert(sl->subLinkId == list_length(ma_sublinks)); + } + } + } + } + next_ma_cell = list_head(ma_sublinks); + cur_ma_sublink = NULL; + remaining_ma_columns = 0; + + /* Add the comma separated list of 'attname = value' */ + sep = ""; + foreach(l, targetList) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + Node *expr; + + if (tle->resjunk) + continue; /* ignore junk entries */ + + /* Emit separator (OK whether we're in multiassignment or not) */ + appendStringInfoString(buf, sep); + sep = ", "; + + /* + * Check to see if we're starting a multiassignment group: if so, + * output a left paren. + */ + if (next_ma_cell != NULL && cur_ma_sublink == NULL) + { + /* + * We must dig down into the expr to see if it's a PARAM_MULTIEXPR + * Param. That could be buried under FieldStores and + * SubscriptingRefs and CoerceToDomains (cf processIndirection()), + * and underneath those there could be an implicit type coercion. + * Because we would ignore implicit type coercions anyway, we + * don't need to be as careful as processIndirection() is about + * descending past implicit CoerceToDomains. + */ + expr = (Node *) tle->expr; + while (expr) + { + if (IsA(expr, FieldStore)) + { + FieldStore *fstore = (FieldStore *) expr; + + expr = (Node *) linitial(fstore->newvals); + } + else if (IsA(expr, SubscriptingRef)) + { + SubscriptingRef *sbsref = (SubscriptingRef *) expr; + + if (sbsref->refassgnexpr == NULL) + break; + + expr = (Node *) sbsref->refassgnexpr; + } + else if (IsA(expr, CoerceToDomain)) + { + CoerceToDomain *cdomain = (CoerceToDomain *) expr; + + if (cdomain->coercionformat != COERCE_IMPLICIT_CAST) + break; + expr = (Node *) cdomain->arg; + } + else + break; + } + expr = strip_implicit_coercions(expr); + + if (expr && IsA(expr, Param) && + ((Param *) expr)->paramkind == PARAM_MULTIEXPR) + { + cur_ma_sublink = (SubLink *) lfirst(next_ma_cell); + next_ma_cell = lnext(ma_sublinks, next_ma_cell); + remaining_ma_columns = count_nonjunk_tlist_entries(((Query *) cur_ma_sublink->subselect)->targetList); + Assert(((Param *) expr)->paramid == + ((cur_ma_sublink->subLinkId << 16) | 1)); + appendStringInfoChar(buf, '('); + } + } + + /* + * Put out name of target column; look in the catalogs, not at + * tle->resname, since resname will fail to track RENAME. + */ + appendStringInfoString(buf, + quote_identifier(get_attname(rte->relid, + tle->resno, + false))); + + /* + * Print any indirection needed (subfields or subscripts), and strip + * off the top-level nodes representing the indirection assignments. + */ + expr = processIndirection((Node *) tle->expr, context); + + /* + * If we're in a multiassignment, skip printing anything more, unless + * this is the last column; in which case, what we print should be the + * sublink, not the Param. + */ + if (cur_ma_sublink != NULL) + { + if (--remaining_ma_columns > 0) + continue; /* not the last column of multiassignment */ + appendStringInfoChar(buf, ')'); + expr = (Node *) cur_ma_sublink; + cur_ma_sublink = NULL; + } + + appendStringInfoString(buf, " = "); + + get_rule_expr(expr, context, false); + } +} + + +/* ---------- + * get_delete_query_def - Parse back a DELETE parsetree + * ---------- + */ +static void +get_delete_query_def(Query *query, deparse_context *context, + bool colNamesVisible) +{ + StringInfo buf = context->buf; + RangeTblEntry *rte; + + /* Insert the WITH clause if given */ + get_with_clause(query, context); + + /* + * Start the query with DELETE FROM relname + */ + rte = rt_fetch(query->resultRelation, query->rtable); + Assert(rte->rtekind == RTE_RELATION); + if (PRETTY_INDENT(context)) + { + appendStringInfoChar(buf, ' '); + context->indentLevel += PRETTYINDENT_STD; + } + appendStringInfo(buf, "DELETE FROM %s%s", + only_marker(rte), + generate_relation_name(rte->relid, NIL)); + if (rte->alias != NULL) + appendStringInfo(buf, " %s", + quote_identifier(rte->alias->aliasname)); + + /* Add the USING clause if given */ + get_from_clause(query, " USING ", context); + + /* Add a WHERE clause if given */ + if (query->jointree->quals != NULL) + { + appendContextKeyword(context, " WHERE ", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_rule_expr(query->jointree->quals, context, false); + } + + /* Add RETURNING if present */ + if (query->returningList) + { + appendContextKeyword(context, " RETURNING", + -PRETTYINDENT_STD, PRETTYINDENT_STD, 1); + get_target_list(query->returningList, context, NULL, colNamesVisible); + } +} + + +/* ---------- + * get_utility_query_def - Parse back a UTILITY parsetree + * ---------- + */ +static void +get_utility_query_def(Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + + if (query->utilityStmt && IsA(query->utilityStmt, NotifyStmt)) + { + NotifyStmt *stmt = (NotifyStmt *) query->utilityStmt; + + appendContextKeyword(context, "", + 0, PRETTYINDENT_STD, 1); + appendStringInfo(buf, "NOTIFY %s", + quote_identifier(stmt->conditionname)); + if (stmt->payload) + { + appendStringInfoString(buf, ", "); + simple_quote_literal(buf, stmt->payload); + } + } + else + { + /* Currently only NOTIFY utility commands can appear in rules */ + elog(ERROR, "unexpected utility statement type"); + } +} + +/* + * Display a Var appropriately. + * + * In some cases (currently only when recursing into an unnamed join) + * the Var's varlevelsup has to be interpreted with respect to a context + * above the current one; levelsup indicates the offset. + * + * If istoplevel is true, the Var is at the top level of a SELECT's + * targetlist, which means we need special treatment of whole-row Vars. + * Instead of the normal "tab.*", we'll print "tab.*::typename", which is a + * dirty hack to prevent "tab.*" from being expanded into multiple columns. + * (The parser will strip the useless coercion, so no inefficiency is added in + * dump and reload.) We used to print just "tab" in such cases, but that is + * ambiguous and will yield the wrong result if "tab" is also a plain column + * name in the query. + * + * Returns the attname of the Var, or NULL if the Var has no attname (because + * it is a whole-row Var or a subplan output reference). + */ +static char * +get_variable(Var *var, int levelsup, bool istoplevel, deparse_context *context) +{ + StringInfo buf = context->buf; + RangeTblEntry *rte; + AttrNumber attnum; + int netlevelsup; + deparse_namespace *dpns; + Index varno; + AttrNumber varattno; + deparse_columns *colinfo; + char *refname; + char *attname; + + /* Find appropriate nesting depth */ + netlevelsup = var->varlevelsup + levelsup; + if (netlevelsup >= list_length(context->namespaces)) + elog(ERROR, "bogus varlevelsup: %d offset %d", + var->varlevelsup, levelsup); + dpns = (deparse_namespace *) list_nth(context->namespaces, + netlevelsup); + + /* + * If we have a syntactic referent for the Var, and we're working from a + * parse tree, prefer to use the syntactic referent. Otherwise, fall back + * on the semantic referent. (Forcing use of the semantic referent when + * printing plan trees is a design choice that's perhaps more motivated by + * backwards compatibility than anything else. But it does have the + * advantage of making plans more explicit.) + */ + if (var->varnosyn > 0 && dpns->plan == NULL) + { + varno = var->varnosyn; + varattno = var->varattnosyn; + } + else + { + varno = var->varno; + varattno = var->varattno; + } + + /* + * Try to find the relevant RTE in this rtable. In a plan tree, it's + * likely that varno is OUTER_VAR or INNER_VAR, in which case we must dig + * down into the subplans, or INDEX_VAR, which is resolved similarly. Also + * find the aliases previously assigned for this RTE. + */ + if (varno >= 1 && varno <= list_length(dpns->rtable)) + { + /* + * We might have been asked to map child Vars to some parent relation. + */ + if (context->appendparents && dpns->appendrels) + { + Index pvarno = varno; + AttrNumber pvarattno = varattno; + AppendRelInfo *appinfo = dpns->appendrels[pvarno]; + bool found = false; + + /* Only map up to inheritance parents, not UNION ALL appendrels */ + while (appinfo && + rt_fetch(appinfo->parent_relid, + dpns->rtable)->rtekind == RTE_RELATION) + { + found = false; + if (pvarattno > 0) /* system columns stay as-is */ + { + if (pvarattno > appinfo->num_child_cols) + break; /* safety check */ + pvarattno = appinfo->parent_colnos[pvarattno - 1]; + if (pvarattno == 0) + break; /* Var is local to child */ + } + + pvarno = appinfo->parent_relid; + found = true; + + /* If the parent is itself a child, continue up. */ + Assert(pvarno > 0 && pvarno <= list_length(dpns->rtable)); + appinfo = dpns->appendrels[pvarno]; + } + + /* + * If we found an ancestral rel, and that rel is included in + * appendparents, print that column not the original one. + */ + if (found && bms_is_member(pvarno, context->appendparents)) + { + varno = pvarno; + varattno = pvarattno; + } + } + + rte = rt_fetch(varno, dpns->rtable); + refname = (char *) list_nth(dpns->rtable_names, varno - 1); + colinfo = deparse_columns_fetch(varno, dpns); + attnum = varattno; + } + else + { + resolve_special_varno((Node *) var, context, + get_special_variable, NULL); + return NULL; + } + + /* + * The planner will sometimes emit Vars referencing resjunk elements of a + * subquery's target list (this is currently only possible if it chooses + * to generate a "physical tlist" for a SubqueryScan or CteScan node). + * Although we prefer to print subquery-referencing Vars using the + * subquery's alias, that's not possible for resjunk items since they have + * no alias. So in that case, drill down to the subplan and print the + * contents of the referenced tlist item. This works because in a plan + * tree, such Vars can only occur in a SubqueryScan or CteScan node, and + * we'll have set dpns->inner_plan to reference the child plan node. + */ + if ((rte->rtekind == RTE_SUBQUERY || rte->rtekind == RTE_CTE) && + attnum > list_length(rte->eref->colnames) && + dpns->inner_plan) + { + TargetEntry *tle; + deparse_namespace save_dpns; + + tle = get_tle_by_resno(dpns->inner_tlist, attnum); + if (!tle) + elog(ERROR, "invalid attnum %d for relation \"%s\"", + attnum, rte->eref->aliasname); + + Assert(netlevelsup == 0); + push_child_plan(dpns, dpns->inner_plan, &save_dpns); + + /* + * Force parentheses because our caller probably assumed a Var is a + * simple expression. + */ + if (!IsA(tle->expr, Var)) + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) tle->expr, context, true); + if (!IsA(tle->expr, Var)) + appendStringInfoChar(buf, ')'); + + pop_child_plan(dpns, &save_dpns); + return NULL; + } + + /* + * If it's an unnamed join, look at the expansion of the alias variable. + * If it's a simple reference to one of the input vars, then recursively + * print the name of that var instead. When it's not a simple reference, + * we have to just print the unqualified join column name. (This can only + * happen with "dangerous" merged columns in a JOIN USING; we took pains + * previously to make the unqualified column name unique in such cases.) + * + * This wouldn't work in decompiling plan trees, because we don't store + * joinaliasvars lists after planning; but a plan tree should never + * contain a join alias variable. + */ + if (rte->rtekind == RTE_JOIN && rte->alias == NULL) + { + if (rte->joinaliasvars == NIL) + elog(ERROR, "cannot decompile join alias var in plan tree"); + if (attnum > 0) + { + Var *aliasvar; + + aliasvar = (Var *) list_nth(rte->joinaliasvars, attnum - 1); + /* we intentionally don't strip implicit coercions here */ + if (aliasvar && IsA(aliasvar, Var)) + { + return get_variable(aliasvar, var->varlevelsup + levelsup, + istoplevel, context); + } + } + + /* + * Unnamed join has no refname. (Note: since it's unnamed, there is + * no way the user could have referenced it to create a whole-row Var + * for it. So we don't have to cover that case below.) + */ + Assert(refname == NULL); + } + + if (attnum == InvalidAttrNumber) + attname = NULL; + else if (attnum > 0) + { + /* Get column name to use from the colinfo struct */ + if (attnum > colinfo->num_cols) + elog(ERROR, "invalid attnum %d for relation \"%s\"", + attnum, rte->eref->aliasname); + attname = colinfo->colnames[attnum - 1]; + + /* + * If we find a Var referencing a dropped column, it seems better to + * print something (anything) than to fail. In general this should + * not happen, but there are specific cases involving functions + * returning named composite types where we don't sufficiently enforce + * that you can't drop a column that's referenced in some view. + */ + if (attname == NULL) + attname = "?dropped?column?"; + } + else + { + /* System column - name is fixed, get it from the catalog */ + attname = get_rte_attribute_name(rte, attnum); + } + + if (refname && (context->varprefix || attname == NULL)) + { + appendStringInfoString(buf, quote_identifier(refname)); + appendStringInfoChar(buf, '.'); + } + if (attname) + appendStringInfoString(buf, quote_identifier(attname)); + else + { + appendStringInfoChar(buf, '*'); + if (istoplevel) + appendStringInfo(buf, "::%s", + format_type_with_typemod(var->vartype, + var->vartypmod)); + } + + return attname; +} + +/* + * Deparse a Var which references OUTER_VAR, INNER_VAR, or INDEX_VAR. This + * routine is actually a callback for resolve_special_varno, which handles + * finding the correct TargetEntry. We get the expression contained in that + * TargetEntry and just need to deparse it, a job we can throw back on + * get_rule_expr. + */ +static void +get_special_variable(Node *node, deparse_context *context, void *callback_arg) +{ + StringInfo buf = context->buf; + + /* + * For a non-Var referent, force parentheses because our caller probably + * assumed a Var is a simple expression. + */ + if (!IsA(node, Var)) + appendStringInfoChar(buf, '('); + get_rule_expr(node, context, true); + if (!IsA(node, Var)) + appendStringInfoChar(buf, ')'); +} + +/* + * Chase through plan references to special varnos (OUTER_VAR, INNER_VAR, + * INDEX_VAR) until we find a real Var or some kind of non-Var node; then, + * invoke the callback provided. + */ +static void +resolve_special_varno(Node *node, deparse_context *context, + rsv_callback callback, void *callback_arg) +{ + Var *var; + deparse_namespace *dpns; + + /* This function is recursive, so let's be paranoid. */ + check_stack_depth(); + + /* If it's not a Var, invoke the callback. */ + if (!IsA(node, Var)) + { + (*callback) (node, context, callback_arg); + return; + } + + /* Find appropriate nesting depth */ + var = (Var *) node; + dpns = (deparse_namespace *) list_nth(context->namespaces, + var->varlevelsup); + + /* + * If varno is special, recurse. (Don't worry about varnosyn; if we're + * here, we already decided not to use that.) + */ + if (var->varno == OUTER_VAR && dpns->outer_tlist) + { + TargetEntry *tle; + deparse_namespace save_dpns; + Bitmapset *save_appendparents; + + tle = get_tle_by_resno(dpns->outer_tlist, var->varattno); + if (!tle) + elog(ERROR, "bogus varattno for OUTER_VAR var: %d", var->varattno); + + /* + * If we're descending to the first child of an Append or MergeAppend, + * update appendparents. This will affect deparsing of all Vars + * appearing within the eventually-resolved subexpression. + */ + save_appendparents = context->appendparents; + + if (IsA(dpns->plan, Append)) + context->appendparents = bms_union(context->appendparents, + ((Append *) dpns->plan)->apprelids); + else if (IsA(dpns->plan, MergeAppend)) + context->appendparents = bms_union(context->appendparents, + ((MergeAppend *) dpns->plan)->apprelids); + + push_child_plan(dpns, dpns->outer_plan, &save_dpns); + resolve_special_varno((Node *) tle->expr, context, + callback, callback_arg); + pop_child_plan(dpns, &save_dpns); + context->appendparents = save_appendparents; + return; + } + else if (var->varno == INNER_VAR && dpns->inner_tlist) + { + TargetEntry *tle; + deparse_namespace save_dpns; + + tle = get_tle_by_resno(dpns->inner_tlist, var->varattno); + if (!tle) + elog(ERROR, "bogus varattno for INNER_VAR var: %d", var->varattno); + + push_child_plan(dpns, dpns->inner_plan, &save_dpns); + resolve_special_varno((Node *) tle->expr, context, + callback, callback_arg); + pop_child_plan(dpns, &save_dpns); + return; + } + else if (var->varno == INDEX_VAR && dpns->index_tlist) + { + TargetEntry *tle; + + tle = get_tle_by_resno(dpns->index_tlist, var->varattno); + if (!tle) + elog(ERROR, "bogus varattno for INDEX_VAR var: %d", var->varattno); + + resolve_special_varno((Node *) tle->expr, context, + callback, callback_arg); + return; + } + else if (var->varno < 1 || var->varno > list_length(dpns->rtable)) + elog(ERROR, "bogus varno: %d", var->varno); + + /* Not special. Just invoke the callback. */ + (*callback) (node, context, callback_arg); +} + +/* + * Get the name of a field of an expression of composite type. The + * expression is usually a Var, but we handle other cases too. + * + * levelsup is an extra offset to interpret the Var's varlevelsup correctly. + * + * This is fairly straightforward when the expression has a named composite + * type; we need only look up the type in the catalogs. However, the type + * could also be RECORD. Since no actual table or view column is allowed to + * have type RECORD, a Var of type RECORD must refer to a JOIN or FUNCTION RTE + * or to a subquery output. We drill down to find the ultimate defining + * expression and attempt to infer the field name from it. We ereport if we + * can't determine the name. + * + * Similarly, a PARAM of type RECORD has to refer to some expression of + * a determinable composite type. + */ +static const char * +get_name_for_var_field(Var *var, int fieldno, + int levelsup, deparse_context *context) +{ + RangeTblEntry *rte; + AttrNumber attnum; + int netlevelsup; + deparse_namespace *dpns; + Index varno; + AttrNumber varattno; + TupleDesc tupleDesc; + Node *expr; + + /* + * If it's a RowExpr that was expanded from a whole-row Var, use the + * column names attached to it. + */ + if (IsA(var, RowExpr)) + { + RowExpr *r = (RowExpr *) var; + + if (fieldno > 0 && fieldno <= list_length(r->colnames)) + return strVal(list_nth(r->colnames, fieldno - 1)); + } + + /* + * If it's a Param of type RECORD, try to find what the Param refers to. + */ + if (IsA(var, Param)) + { + Param *param = (Param *) var; + ListCell *ancestor_cell; + + expr = find_param_referent(param, context, &dpns, &ancestor_cell); + if (expr) + { + /* Found a match, so recurse to decipher the field name */ + deparse_namespace save_dpns; + const char *result; + + push_ancestor_plan(dpns, ancestor_cell, &save_dpns); + result = get_name_for_var_field((Var *) expr, fieldno, + 0, context); + pop_ancestor_plan(dpns, &save_dpns); + return result; + } + } + + /* + * If it's a Var of type RECORD, we have to find what the Var refers to; + * if not, we can use get_expr_result_tupdesc(). + */ + if (!IsA(var, Var) || + var->vartype != RECORDOID) + { + tupleDesc = get_expr_result_tupdesc((Node *) var, false); + /* Got the tupdesc, so we can extract the field name */ + Assert(fieldno >= 1 && fieldno <= tupleDesc->natts); + return NameStr(TupleDescAttr(tupleDesc, fieldno - 1)->attname); + } + + /* Find appropriate nesting depth */ + netlevelsup = var->varlevelsup + levelsup; + if (netlevelsup >= list_length(context->namespaces)) + elog(ERROR, "bogus varlevelsup: %d offset %d", + var->varlevelsup, levelsup); + dpns = (deparse_namespace *) list_nth(context->namespaces, + netlevelsup); + + /* + * If we have a syntactic referent for the Var, and we're working from a + * parse tree, prefer to use the syntactic referent. Otherwise, fall back + * on the semantic referent. (See comments in get_variable().) + */ + if (var->varnosyn > 0 && dpns->plan == NULL) + { + varno = var->varnosyn; + varattno = var->varattnosyn; + } + else + { + varno = var->varno; + varattno = var->varattno; + } + + /* + * Try to find the relevant RTE in this rtable. In a plan tree, it's + * likely that varno is OUTER_VAR or INNER_VAR, in which case we must dig + * down into the subplans, or INDEX_VAR, which is resolved similarly. + * + * Note: unlike get_variable and resolve_special_varno, we need not worry + * about inheritance mapping: a child Var should have the same datatype as + * its parent, and here we're really only interested in the Var's type. + */ + if (varno >= 1 && varno <= list_length(dpns->rtable)) + { + rte = rt_fetch(varno, dpns->rtable); + attnum = varattno; + } + else if (varno == OUTER_VAR && dpns->outer_tlist) + { + TargetEntry *tle; + deparse_namespace save_dpns; + const char *result; + + tle = get_tle_by_resno(dpns->outer_tlist, varattno); + if (!tle) + elog(ERROR, "bogus varattno for OUTER_VAR var: %d", varattno); + + Assert(netlevelsup == 0); + push_child_plan(dpns, dpns->outer_plan, &save_dpns); + + result = get_name_for_var_field((Var *) tle->expr, fieldno, + levelsup, context); + + pop_child_plan(dpns, &save_dpns); + return result; + } + else if (varno == INNER_VAR && dpns->inner_tlist) + { + TargetEntry *tle; + deparse_namespace save_dpns; + const char *result; + + tle = get_tle_by_resno(dpns->inner_tlist, varattno); + if (!tle) + elog(ERROR, "bogus varattno for INNER_VAR var: %d", varattno); + + Assert(netlevelsup == 0); + push_child_plan(dpns, dpns->inner_plan, &save_dpns); + + result = get_name_for_var_field((Var *) tle->expr, fieldno, + levelsup, context); + + pop_child_plan(dpns, &save_dpns); + return result; + } + else if (varno == INDEX_VAR && dpns->index_tlist) + { + TargetEntry *tle; + const char *result; + + tle = get_tle_by_resno(dpns->index_tlist, varattno); + if (!tle) + elog(ERROR, "bogus varattno for INDEX_VAR var: %d", varattno); + + Assert(netlevelsup == 0); + + result = get_name_for_var_field((Var *) tle->expr, fieldno, + levelsup, context); + + return result; + } + else + { + elog(ERROR, "bogus varno: %d", varno); + return NULL; /* keep compiler quiet */ + } + + if (attnum == InvalidAttrNumber) + { + /* Var is whole-row reference to RTE, so select the right field */ + return get_rte_attribute_name(rte, fieldno); + } + + /* + * This part has essentially the same logic as the parser's + * expandRecordVariable() function, but we are dealing with a different + * representation of the input context, and we only need one field name + * not a TupleDesc. Also, we need special cases for finding subquery and + * CTE subplans when deparsing Plan trees. + */ + expr = (Node *) var; /* default if we can't drill down */ + + switch (rte->rtekind) + { + case RTE_RELATION: + case RTE_VALUES: + case RTE_NAMEDTUPLESTORE: + case RTE_RESULT: + + /* + * This case should not occur: a column of a table, values list, + * or ENR shouldn't have type RECORD. Fall through and fail (most + * likely) at the bottom. + */ + break; + case RTE_SUBQUERY: + /* Subselect-in-FROM: examine sub-select's output expr */ + { + if (rte->subquery) + { + TargetEntry *ste = get_tle_by_resno(rte->subquery->targetList, + attnum); + + if (ste == NULL || ste->resjunk) + elog(ERROR, "subquery %s does not have attribute %d", + rte->eref->aliasname, attnum); + expr = (Node *) ste->expr; + if (IsA(expr, Var)) + { + /* + * Recurse into the sub-select to see what its Var + * refers to. We have to build an additional level of + * namespace to keep in step with varlevelsup in the + * subselect. + */ + deparse_namespace mydpns; + const char *result; + + set_deparse_for_query(&mydpns, rte->subquery, + context->namespaces); + + context->namespaces = lcons(&mydpns, + context->namespaces); + + result = get_name_for_var_field((Var *) expr, fieldno, + 0, context); + + context->namespaces = + list_delete_first(context->namespaces); + + return result; + } + /* else fall through to inspect the expression */ + } + else + { + /* + * We're deparsing a Plan tree so we don't have complete + * RTE entries (in particular, rte->subquery is NULL). But + * the only place we'd see a Var directly referencing a + * SUBQUERY RTE is in a SubqueryScan plan node, and we can + * look into the child plan's tlist instead. + */ + TargetEntry *tle; + deparse_namespace save_dpns; + const char *result; + + if (!dpns->inner_plan) + elog(ERROR, "failed to find plan for subquery %s", + rte->eref->aliasname); + tle = get_tle_by_resno(dpns->inner_tlist, attnum); + if (!tle) + elog(ERROR, "bogus varattno for subquery var: %d", + attnum); + Assert(netlevelsup == 0); + push_child_plan(dpns, dpns->inner_plan, &save_dpns); + + result = get_name_for_var_field((Var *) tle->expr, fieldno, + levelsup, context); + + pop_child_plan(dpns, &save_dpns); + return result; + } + } + break; + case RTE_JOIN: + /* Join RTE --- recursively inspect the alias variable */ + if (rte->joinaliasvars == NIL) + elog(ERROR, "cannot decompile join alias var in plan tree"); + Assert(attnum > 0 && attnum <= list_length(rte->joinaliasvars)); + expr = (Node *) list_nth(rte->joinaliasvars, attnum - 1); + Assert(expr != NULL); + /* we intentionally don't strip implicit coercions here */ + if (IsA(expr, Var)) + return get_name_for_var_field((Var *) expr, fieldno, + var->varlevelsup + levelsup, + context); + /* else fall through to inspect the expression */ + break; + case RTE_FUNCTION: + case RTE_TABLEFUNC: + + /* + * We couldn't get here unless a function is declared with one of + * its result columns as RECORD, which is not allowed. + */ + break; + case RTE_CTE: + /* CTE reference: examine subquery's output expr */ + { + CommonTableExpr *cte = NULL; + Index ctelevelsup; + ListCell *lc; + + /* + * Try to find the referenced CTE using the namespace stack. + */ + ctelevelsup = rte->ctelevelsup + netlevelsup; + if (ctelevelsup >= list_length(context->namespaces)) + lc = NULL; + else + { + deparse_namespace *ctedpns; + + ctedpns = (deparse_namespace *) + list_nth(context->namespaces, ctelevelsup); + foreach(lc, ctedpns->ctes) + { + cte = (CommonTableExpr *) lfirst(lc); + if (strcmp(cte->ctename, rte->ctename) == 0) + break; + } + } + if (lc != NULL) + { + Query *ctequery = (Query *) cte->ctequery; + TargetEntry *ste = get_tle_by_resno(GetCTETargetList(cte), + attnum); + + if (ste == NULL || ste->resjunk) + elog(ERROR, "subquery %s does not have attribute %d", + rte->eref->aliasname, attnum); + expr = (Node *) ste->expr; + if (IsA(expr, Var)) + { + /* + * Recurse into the CTE to see what its Var refers to. + * We have to build an additional level of namespace + * to keep in step with varlevelsup in the CTE. + * Furthermore it could be an outer CTE, so we may + * have to delete some levels of namespace. + */ + List *save_nslist = context->namespaces; + List *new_nslist; + deparse_namespace mydpns; + const char *result; + + set_deparse_for_query(&mydpns, ctequery, + context->namespaces); + + new_nslist = list_copy_tail(context->namespaces, + ctelevelsup); + context->namespaces = lcons(&mydpns, new_nslist); + + result = get_name_for_var_field((Var *) expr, fieldno, + 0, context); + + context->namespaces = save_nslist; + + return result; + } + /* else fall through to inspect the expression */ + } + else + { + /* + * We're deparsing a Plan tree so we don't have a CTE + * list. But the only places we'd see a Var directly + * referencing a CTE RTE are in CteScan or WorkTableScan + * plan nodes. For those cases, set_deparse_plan arranged + * for dpns->inner_plan to be the plan node that emits the + * CTE or RecursiveUnion result, and we can look at its + * tlist instead. + */ + TargetEntry *tle; + deparse_namespace save_dpns; + const char *result; + + if (!dpns->inner_plan) + elog(ERROR, "failed to find plan for CTE %s", + rte->eref->aliasname); + tle = get_tle_by_resno(dpns->inner_tlist, attnum); + if (!tle) + elog(ERROR, "bogus varattno for subquery var: %d", + attnum); + Assert(netlevelsup == 0); + push_child_plan(dpns, dpns->inner_plan, &save_dpns); + + result = get_name_for_var_field((Var *) tle->expr, fieldno, + levelsup, context); + + pop_child_plan(dpns, &save_dpns); + return result; + } + } + break; + } + + /* + * We now have an expression we can't expand any more, so see if + * get_expr_result_tupdesc() can do anything with it. + */ + tupleDesc = get_expr_result_tupdesc(expr, false); + /* Got the tupdesc, so we can extract the field name */ + Assert(fieldno >= 1 && fieldno <= tupleDesc->natts); + return NameStr(TupleDescAttr(tupleDesc, fieldno - 1)->attname); +} + +/* + * Try to find the referenced expression for a PARAM_EXEC Param that might + * reference a parameter supplied by an upper NestLoop or SubPlan plan node. + * + * If successful, return the expression and set *dpns_p and *ancestor_cell_p + * appropriately for calling push_ancestor_plan(). If no referent can be + * found, return NULL. + */ +static Node * +find_param_referent(Param *param, deparse_context *context, + deparse_namespace **dpns_p, ListCell **ancestor_cell_p) +{ + /* Initialize output parameters to prevent compiler warnings */ + *dpns_p = NULL; + *ancestor_cell_p = NULL; + + /* + * If it's a PARAM_EXEC parameter, look for a matching NestLoopParam or + * SubPlan argument. This will necessarily be in some ancestor of the + * current expression's Plan node. + */ + if (param->paramkind == PARAM_EXEC) + { + deparse_namespace *dpns; + Plan *child_plan; + bool in_same_plan_level; + ListCell *lc; + + dpns = (deparse_namespace *) linitial(context->namespaces); + child_plan = dpns->plan; + in_same_plan_level = true; + + foreach(lc, dpns->ancestors) + { + Node *ancestor = (Node *) lfirst(lc); + ListCell *lc2; + + /* + * NestLoops transmit params to their inner child only; also, once + * we've crawled up out of a subplan, this couldn't possibly be + * the right match. + */ + if (IsA(ancestor, NestLoop) && + child_plan == innerPlan(ancestor) && + in_same_plan_level) + { + NestLoop *nl = (NestLoop *) ancestor; + + foreach(lc2, nl->nestParams) + { + NestLoopParam *nlp = (NestLoopParam *) lfirst(lc2); + + if (nlp->paramno == param->paramid) + { + /* Found a match, so return it */ + *dpns_p = dpns; + *ancestor_cell_p = lc; + return (Node *) nlp->paramval; + } + } + } + + /* + * If ancestor is a SubPlan, check the arguments it provides. + */ + if (IsA(ancestor, SubPlan)) + { + SubPlan *subplan = (SubPlan *) ancestor; + ListCell *lc3; + ListCell *lc4; + + forboth(lc3, subplan->parParam, lc4, subplan->args) + { + int paramid = lfirst_int(lc3); + Node *arg = (Node *) lfirst(lc4); + + if (paramid == param->paramid) + { + /* + * Found a match, so return it. But, since Vars in + * the arg are to be evaluated in the surrounding + * context, we have to point to the next ancestor item + * that is *not* a SubPlan. + */ + ListCell *rest; + + for_each_cell(rest, dpns->ancestors, + lnext(dpns->ancestors, lc)) + { + Node *ancestor2 = (Node *) lfirst(rest); + + if (!IsA(ancestor2, SubPlan)) + { + *dpns_p = dpns; + *ancestor_cell_p = rest; + return arg; + } + } + elog(ERROR, "SubPlan cannot be outermost ancestor"); + } + } + + /* We have emerged from a subplan. */ + in_same_plan_level = false; + + /* SubPlan isn't a kind of Plan, so skip the rest */ + continue; + } + + /* + * Check to see if we're emerging from an initplan of the current + * ancestor plan. Initplans never have any parParams, so no need + * to search that list, but we need to know if we should reset + * in_same_plan_level. + */ + foreach(lc2, ((Plan *) ancestor)->initPlan) + { + SubPlan *subplan = castNode(SubPlan, lfirst(lc2)); + + if (child_plan != (Plan *) list_nth(dpns->subplans, + subplan->plan_id - 1)) + continue; + + /* No parameters to be had here. */ + Assert(subplan->parParam == NIL); + + /* We have emerged from an initplan. */ + in_same_plan_level = false; + break; + } + + /* No luck, crawl up to next ancestor */ + child_plan = (Plan *) ancestor; + } + } + + /* No referent found */ + return NULL; +} + +/* + * Display a Param appropriately. + */ +static void +get_parameter(Param *param, deparse_context *context) +{ + Node *expr; + deparse_namespace *dpns; + ListCell *ancestor_cell; + + /* + * If it's a PARAM_EXEC parameter, try to locate the expression from which + * the parameter was computed. Note that failing to find a referent isn't + * an error, since the Param might well be a subplan output rather than an + * input. + */ + expr = find_param_referent(param, context, &dpns, &ancestor_cell); + if (expr) + { + /* Found a match, so print it */ + deparse_namespace save_dpns; + bool save_varprefix; + bool need_paren; + + /* Switch attention to the ancestor plan node */ + push_ancestor_plan(dpns, ancestor_cell, &save_dpns); + + /* + * Force prefixing of Vars, since they won't belong to the relation + * being scanned in the original plan node. + */ + save_varprefix = context->varprefix; + context->varprefix = true; + + /* + * A Param's expansion is typically a Var, Aggref, GroupingFunc, or + * upper-level Param, which wouldn't need extra parentheses. + * Otherwise, insert parens to ensure the expression looks atomic. + */ + need_paren = !(IsA(expr, Var) || + IsA(expr, Aggref) || + IsA(expr, GroupingFunc) || + IsA(expr, Param)); + if (need_paren) + appendStringInfoChar(context->buf, '('); + + get_rule_expr(expr, context, false); + + if (need_paren) + appendStringInfoChar(context->buf, ')'); + + context->varprefix = save_varprefix; + + pop_ancestor_plan(dpns, &save_dpns); + + return; + } + + /* + * If it's an external parameter, see if the outermost namespace provides + * function argument names. + */ + if (param->paramkind == PARAM_EXTERN && context->namespaces != NIL) + { + dpns = llast(context->namespaces); + if (dpns->argnames && + param->paramid > 0 && + param->paramid <= dpns->numargs) + { + char *argname = dpns->argnames[param->paramid - 1]; + + if (argname) + { + bool should_qualify = false; + ListCell *lc; + + /* + * Qualify the parameter name if there are any other deparse + * namespaces with range tables. This avoids qualifying in + * trivial cases like "RETURN a + b", but makes it safe in all + * other cases. + */ + foreach(lc, context->namespaces) + { + deparse_namespace *dpns = lfirst(lc); + + if (list_length(dpns->rtable_names) > 0) + { + should_qualify = true; + break; + } + } + if (should_qualify) + { + appendStringInfoString(context->buf, quote_identifier(dpns->funcname)); + appendStringInfoChar(context->buf, '.'); + } + + appendStringInfoString(context->buf, quote_identifier(argname)); + return; + } + } + } + + /* + * Not PARAM_EXEC, or couldn't find referent: just print $N. + */ + appendStringInfo(context->buf, "$%d", param->paramid); +} + +/* + * get_simple_binary_op_name + * + * helper function for isSimpleNode + * will return single char binary operator name, or NULL if it's not + */ +static const char * +get_simple_binary_op_name(OpExpr *expr) +{ + List *args = expr->args; + + if (list_length(args) == 2) + { + /* binary operator */ + Node *arg1 = (Node *) linitial(args); + Node *arg2 = (Node *) lsecond(args); + const char *op; + + op = generate_operator_name(expr->opno, exprType(arg1), exprType(arg2)); + if (strlen(op) == 1) + return op; + } + return NULL; +} + + +/* + * isSimpleNode - check if given node is simple (doesn't need parenthesizing) + * + * true : simple in the context of parent node's type + * false : not simple + */ +static bool +isSimpleNode(Node *node, Node *parentNode, int prettyFlags) +{ + if (!node) + return false; + + switch (nodeTag(node)) + { + case T_Var: + case T_Const: + case T_Param: + case T_CoerceToDomainValue: + case T_SetToDefault: + case T_CurrentOfExpr: + /* single words: always simple */ + return true; + + case T_SubscriptingRef: + case T_ArrayExpr: + case T_RowExpr: + case T_CoalesceExpr: + case T_MinMaxExpr: + case T_SQLValueFunction: + case T_XmlExpr: + case T_NextValueExpr: + case T_NullIfExpr: + case T_Aggref: + case T_GroupingFunc: + case T_WindowFunc: + case T_FuncExpr: + /* function-like: name(..) or name[..] */ + return true; + + /* CASE keywords act as parentheses */ + case T_CaseExpr: + return true; + + case T_FieldSelect: + + /* + * appears simple since . has top precedence, unless parent is + * T_FieldSelect itself! + */ + return (IsA(parentNode, FieldSelect) ? false : true); + + case T_FieldStore: + + /* + * treat like FieldSelect (probably doesn't matter) + */ + return (IsA(parentNode, FieldStore) ? false : true); + + case T_CoerceToDomain: + /* maybe simple, check args */ + return isSimpleNode((Node *) ((CoerceToDomain *) node)->arg, + node, prettyFlags); + case T_RelabelType: + return isSimpleNode((Node *) ((RelabelType *) node)->arg, + node, prettyFlags); + case T_CoerceViaIO: + return isSimpleNode((Node *) ((CoerceViaIO *) node)->arg, + node, prettyFlags); + case T_ArrayCoerceExpr: + return isSimpleNode((Node *) ((ArrayCoerceExpr *) node)->arg, + node, prettyFlags); + case T_ConvertRowtypeExpr: + return isSimpleNode((Node *) ((ConvertRowtypeExpr *) node)->arg, + node, prettyFlags); + + case T_OpExpr: + { + /* depends on parent node type; needs further checking */ + if (prettyFlags & PRETTYFLAG_PAREN && IsA(parentNode, OpExpr)) + { + const char *op; + const char *parentOp; + bool is_lopriop; + bool is_hipriop; + bool is_lopriparent; + bool is_hipriparent; + + op = get_simple_binary_op_name((OpExpr *) node); + if (!op) + return false; + + /* We know only the basic operators + - and * / % */ + is_lopriop = (strchr("+-", *op) != NULL); + is_hipriop = (strchr("*/%", *op) != NULL); + if (!(is_lopriop || is_hipriop)) + return false; + + parentOp = get_simple_binary_op_name((OpExpr *) parentNode); + if (!parentOp) + return false; + + is_lopriparent = (strchr("+-", *parentOp) != NULL); + is_hipriparent = (strchr("*/%", *parentOp) != NULL); + if (!(is_lopriparent || is_hipriparent)) + return false; + + if (is_hipriop && is_lopriparent) + return true; /* op binds tighter than parent */ + + if (is_lopriop && is_hipriparent) + return false; + + /* + * Operators are same priority --- can skip parens only if + * we have (a - b) - c, not a - (b - c). + */ + if (node == (Node *) linitial(((OpExpr *) parentNode)->args)) + return true; + + return false; + } + /* else do the same stuff as for T_SubLink et al. */ + } + /* FALLTHROUGH */ + + case T_SubLink: + case T_NullTest: + case T_BooleanTest: + case T_DistinctExpr: + switch (nodeTag(parentNode)) + { + case T_FuncExpr: + { + /* special handling for casts */ + CoercionForm type = ((FuncExpr *) parentNode)->funcformat; + + if (type == COERCE_EXPLICIT_CAST || + type == COERCE_IMPLICIT_CAST) + return false; + return true; /* own parentheses */ + } + case T_BoolExpr: /* lower precedence */ + case T_SubscriptingRef: /* other separators */ + case T_ArrayExpr: /* other separators */ + case T_RowExpr: /* other separators */ + case T_CoalesceExpr: /* own parentheses */ + case T_MinMaxExpr: /* own parentheses */ + case T_XmlExpr: /* own parentheses */ + case T_NullIfExpr: /* other separators */ + case T_Aggref: /* own parentheses */ + case T_GroupingFunc: /* own parentheses */ + case T_WindowFunc: /* own parentheses */ + case T_CaseExpr: /* other separators */ + return true; + default: + return false; + } + + case T_BoolExpr: + switch (nodeTag(parentNode)) + { + case T_BoolExpr: + if (prettyFlags & PRETTYFLAG_PAREN) + { + BoolExprType type; + BoolExprType parentType; + + type = ((BoolExpr *) node)->boolop; + parentType = ((BoolExpr *) parentNode)->boolop; + switch (type) + { + case NOT_EXPR: + case AND_EXPR: + if (parentType == AND_EXPR || parentType == OR_EXPR) + return true; + break; + case OR_EXPR: + if (parentType == OR_EXPR) + return true; + break; + } + } + return false; + case T_FuncExpr: + { + /* special handling for casts */ + CoercionForm type = ((FuncExpr *) parentNode)->funcformat; + + if (type == COERCE_EXPLICIT_CAST || + type == COERCE_IMPLICIT_CAST) + return false; + return true; /* own parentheses */ + } + case T_SubscriptingRef: /* other separators */ + case T_ArrayExpr: /* other separators */ + case T_RowExpr: /* other separators */ + case T_CoalesceExpr: /* own parentheses */ + case T_MinMaxExpr: /* own parentheses */ + case T_XmlExpr: /* own parentheses */ + case T_NullIfExpr: /* other separators */ + case T_Aggref: /* own parentheses */ + case T_GroupingFunc: /* own parentheses */ + case T_WindowFunc: /* own parentheses */ + case T_CaseExpr: /* other separators */ + return true; + default: + return false; + } + + default: + break; + } + /* those we don't know: in dubio complexo */ + return false; +} + + +/* + * appendContextKeyword - append a keyword to buffer + * + * If prettyPrint is enabled, perform a line break, and adjust indentation. + * Otherwise, just append the keyword. + */ +static void +appendContextKeyword(deparse_context *context, const char *str, + int indentBefore, int indentAfter, int indentPlus) +{ + StringInfo buf = context->buf; + + if (PRETTY_INDENT(context)) + { + int indentAmount; + + context->indentLevel += indentBefore; + + /* remove any trailing spaces currently in the buffer ... */ + removeStringInfoSpaces(buf); + /* ... then add a newline and some spaces */ + appendStringInfoChar(buf, '\n'); + + if (context->indentLevel < PRETTYINDENT_LIMIT) + indentAmount = Max(context->indentLevel, 0) + indentPlus; + else + { + /* + * If we're indented more than PRETTYINDENT_LIMIT characters, try + * to conserve horizontal space by reducing the per-level + * indentation. For best results the scale factor here should + * divide all the indent amounts that get added to indentLevel + * (PRETTYINDENT_STD, etc). It's important that the indentation + * not grow unboundedly, else deeply-nested trees use O(N^2) + * whitespace; so we also wrap modulo PRETTYINDENT_LIMIT. + */ + indentAmount = PRETTYINDENT_LIMIT + + (context->indentLevel - PRETTYINDENT_LIMIT) / + (PRETTYINDENT_STD / 2); + indentAmount %= PRETTYINDENT_LIMIT; + /* scale/wrap logic affects indentLevel, but not indentPlus */ + indentAmount += indentPlus; + } + appendStringInfoSpaces(buf, indentAmount); + + appendStringInfoString(buf, str); + + context->indentLevel += indentAfter; + if (context->indentLevel < 0) + context->indentLevel = 0; + } + else + appendStringInfoString(buf, str); +} + +/* + * removeStringInfoSpaces - delete trailing spaces from a buffer. + * + * Possibly this should move to stringinfo.c at some point. + */ +static void +removeStringInfoSpaces(StringInfo str) +{ + while (str->len > 0 && str->data[str->len - 1] == ' ') + str->data[--(str->len)] = '\0'; +} + + +/* + * get_rule_expr_paren - deparse expr using get_rule_expr, + * embracing the string with parentheses if necessary for prettyPrint. + * + * Never embrace if prettyFlags=0, because it's done in the calling node. + * + * Any node that does *not* embrace its argument node by sql syntax (with + * parentheses, non-operator keywords like CASE/WHEN/ON, or comma etc) should + * use get_rule_expr_paren instead of get_rule_expr so parentheses can be + * added. + */ +static void +get_rule_expr_paren(Node *node, deparse_context *context, + bool showimplicit, Node *parentNode) +{ + bool need_paren; + + need_paren = PRETTY_PAREN(context) && + !isSimpleNode(node, parentNode, context->prettyFlags); + + if (need_paren) + appendStringInfoChar(context->buf, '('); + + get_rule_expr(node, context, showimplicit); + + if (need_paren) + appendStringInfoChar(context->buf, ')'); +} + + +/* ---------- + * get_rule_expr - Parse back an expression + * + * Note: showimplicit determines whether we display any implicit cast that + * is present at the top of the expression tree. It is a passed argument, + * not a field of the context struct, because we change the value as we + * recurse down into the expression. In general we suppress implicit casts + * when the result type is known with certainty (eg, the arguments of an + * OR must be boolean). We display implicit casts for arguments of functions + * and operators, since this is needed to be certain that the same function + * or operator will be chosen when the expression is re-parsed. + * ---------- + */ +static void +get_rule_expr(Node *node, deparse_context *context, + bool showimplicit) +{ + StringInfo buf = context->buf; + + if (node == NULL) + return; + + /* Guard against excessively long or deeply-nested queries */ + CHECK_FOR_INTERRUPTS(); + check_stack_depth(); + + /* + * Each level of get_rule_expr must emit an indivisible term + * (parenthesized if necessary) to ensure result is reparsed into the same + * expression tree. The only exception is that when the input is a List, + * we emit the component items comma-separated with no surrounding + * decoration; this is convenient for most callers. + */ + switch (nodeTag(node)) + { + case T_Var: + (void) get_variable((Var *) node, 0, false, context); + break; + + case T_Const: + get_const_expr((Const *) node, context, 0); + break; + + case T_Param: + get_parameter((Param *) node, context); + break; + + case T_Aggref: + get_agg_expr((Aggref *) node, context, (Aggref *) node); + break; + + case T_GroupingFunc: + { + GroupingFunc *gexpr = (GroupingFunc *) node; + + appendStringInfoString(buf, "GROUPING("); + get_rule_expr((Node *) gexpr->args, context, true); + appendStringInfoChar(buf, ')'); + } + break; + + case T_WindowFunc: + get_windowfunc_expr((WindowFunc *) node, context); + break; + + case T_SubscriptingRef: + { + SubscriptingRef *sbsref = (SubscriptingRef *) node; + bool need_parens; + + /* + * If the argument is a CaseTestExpr, we must be inside a + * FieldStore, ie, we are assigning to an element of an array + * within a composite column. Since we already punted on + * displaying the FieldStore's target information, just punt + * here too, and display only the assignment source + * expression. + */ + if (IsA(sbsref->refexpr, CaseTestExpr)) + { + Assert(sbsref->refassgnexpr); + get_rule_expr((Node *) sbsref->refassgnexpr, + context, showimplicit); + break; + } + + /* + * Parenthesize the argument unless it's a simple Var or a + * FieldSelect. (In particular, if it's another + * SubscriptingRef, we *must* parenthesize to avoid + * confusion.) + */ + need_parens = !IsA(sbsref->refexpr, Var) && + !IsA(sbsref->refexpr, FieldSelect); + if (need_parens) + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) sbsref->refexpr, context, showimplicit); + if (need_parens) + appendStringInfoChar(buf, ')'); + + /* + * If there's a refassgnexpr, we want to print the node in the + * format "container[subscripts] := refassgnexpr". This is + * not legal SQL, so decompilation of INSERT or UPDATE + * statements should always use processIndirection as part of + * the statement-level syntax. We should only see this when + * EXPLAIN tries to print the targetlist of a plan resulting + * from such a statement. + */ + if (sbsref->refassgnexpr) + { + Node *refassgnexpr; + + /* + * Use processIndirection to print this node's subscripts + * as well as any additional field selections or + * subscripting in immediate descendants. It returns the + * RHS expr that is actually being "assigned". + */ + refassgnexpr = processIndirection(node, context); + appendStringInfoString(buf, " := "); + get_rule_expr(refassgnexpr, context, showimplicit); + } + else + { + /* Just an ordinary container fetch, so print subscripts */ + printSubscripts(sbsref, context); + } + } + break; + + case T_FuncExpr: + get_func_expr((FuncExpr *) node, context, showimplicit); + break; + + case T_NamedArgExpr: + { + NamedArgExpr *na = (NamedArgExpr *) node; + + appendStringInfo(buf, "%s => ", quote_identifier(na->name)); + get_rule_expr((Node *) na->arg, context, showimplicit); + } + break; + + case T_OpExpr: + get_oper_expr((OpExpr *) node, context); + break; + + case T_DistinctExpr: + { + DistinctExpr *expr = (DistinctExpr *) node; + List *args = expr->args; + Node *arg1 = (Node *) linitial(args); + Node *arg2 = (Node *) lsecond(args); + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(arg1, context, true, node); + appendStringInfoString(buf, " IS DISTINCT FROM "); + get_rule_expr_paren(arg2, context, true, node); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + break; + + case T_NullIfExpr: + { + NullIfExpr *nullifexpr = (NullIfExpr *) node; + + appendStringInfoString(buf, "NULLIF("); + get_rule_expr((Node *) nullifexpr->args, context, true); + appendStringInfoChar(buf, ')'); + } + break; + + case T_ScalarArrayOpExpr: + { + ScalarArrayOpExpr *expr = (ScalarArrayOpExpr *) node; + List *args = expr->args; + Node *arg1 = (Node *) linitial(args); + Node *arg2 = (Node *) lsecond(args); + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(arg1, context, true, node); + appendStringInfo(buf, " %s %s (", + generate_operator_name(expr->opno, + exprType(arg1), + get_base_element_type(exprType(arg2))), + expr->useOr ? "ANY" : "ALL"); + get_rule_expr_paren(arg2, context, true, node); + + /* + * There's inherent ambiguity in "x op ANY/ALL (y)" when y is + * a bare sub-SELECT. Since we're here, the sub-SELECT must + * be meant as a scalar sub-SELECT yielding an array value to + * be used in ScalarArrayOpExpr; but the grammar will + * preferentially interpret such a construct as an ANY/ALL + * SubLink. To prevent misparsing the output that way, insert + * a dummy coercion (which will be stripped by parse analysis, + * so no inefficiency is added in dump and reload). This is + * indeed most likely what the user wrote to get the construct + * accepted in the first place. + */ + if (IsA(arg2, SubLink) && + ((SubLink *) arg2)->subLinkType == EXPR_SUBLINK) + appendStringInfo(buf, "::%s", + format_type_with_typemod(exprType(arg2), + exprTypmod(arg2))); + appendStringInfoChar(buf, ')'); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + break; + + case T_BoolExpr: + { + BoolExpr *expr = (BoolExpr *) node; + Node *first_arg = linitial(expr->args); + ListCell *arg; + + switch (expr->boolop) + { + case AND_EXPR: + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(first_arg, context, + false, node); + for_each_from(arg, expr->args, 1) + { + appendStringInfoString(buf, " AND "); + get_rule_expr_paren((Node *) lfirst(arg), context, + false, node); + } + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + break; + + case OR_EXPR: + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(first_arg, context, + false, node); + for_each_from(arg, expr->args, 1) + { + appendStringInfoString(buf, " OR "); + get_rule_expr_paren((Node *) lfirst(arg), context, + false, node); + } + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + break; + + case NOT_EXPR: + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + appendStringInfoString(buf, "NOT "); + get_rule_expr_paren(first_arg, context, + false, node); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + break; + + default: + elog(ERROR, "unrecognized boolop: %d", + (int) expr->boolop); + } + } + break; + + case T_SubLink: + get_sublink_expr((SubLink *) node, context); + break; + + case T_SubPlan: + { + SubPlan *subplan = (SubPlan *) node; + + /* + * We cannot see an already-planned subplan in rule deparsing, + * only while EXPLAINing a query plan. We don't try to + * reconstruct the original SQL, just reference the subplan + * that appears elsewhere in EXPLAIN's result. + */ + if (subplan->useHashTable) + appendStringInfo(buf, "(hashed %s)", subplan->plan_name); + else + appendStringInfo(buf, "(%s)", subplan->plan_name); + } + break; + + case T_AlternativeSubPlan: + { + AlternativeSubPlan *asplan = (AlternativeSubPlan *) node; + ListCell *lc; + + /* + * This case cannot be reached in normal usage, since no + * AlternativeSubPlan can appear either in parsetrees or + * finished plan trees. We keep it just in case somebody + * wants to use this code to print planner data structures. + */ + appendStringInfoString(buf, "(alternatives: "); + foreach(lc, asplan->subplans) + { + SubPlan *splan = lfirst_node(SubPlan, lc); + + if (splan->useHashTable) + appendStringInfo(buf, "hashed %s", splan->plan_name); + else + appendStringInfoString(buf, splan->plan_name); + if (lnext(asplan->subplans, lc)) + appendStringInfoString(buf, " or "); + } + appendStringInfoChar(buf, ')'); + } + break; + + case T_FieldSelect: + { + FieldSelect *fselect = (FieldSelect *) node; + Node *arg = (Node *) fselect->arg; + int fno = fselect->fieldnum; + const char *fieldname; + bool need_parens; + + /* + * Parenthesize the argument unless it's an SubscriptingRef or + * another FieldSelect. Note in particular that it would be + * WRONG to not parenthesize a Var argument; simplicity is not + * the issue here, having the right number of names is. + */ + need_parens = !IsA(arg, SubscriptingRef) && + !IsA(arg, FieldSelect); + if (need_parens) + appendStringInfoChar(buf, '('); + get_rule_expr(arg, context, true); + if (need_parens) + appendStringInfoChar(buf, ')'); + + /* + * Get and print the field name. + */ + fieldname = get_name_for_var_field((Var *) arg, fno, + 0, context); + appendStringInfo(buf, ".%s", quote_identifier(fieldname)); + } + break; + + case T_FieldStore: + { + FieldStore *fstore = (FieldStore *) node; + bool need_parens; + + /* + * There is no good way to represent a FieldStore as real SQL, + * so decompilation of INSERT or UPDATE statements should + * always use processIndirection as part of the + * statement-level syntax. We should only get here when + * EXPLAIN tries to print the targetlist of a plan resulting + * from such a statement. The plan case is even harder than + * ordinary rules would be, because the planner tries to + * collapse multiple assignments to the same field or subfield + * into one FieldStore; so we can see a list of target fields + * not just one, and the arguments could be FieldStores + * themselves. We don't bother to try to print the target + * field names; we just print the source arguments, with a + * ROW() around them if there's more than one. This isn't + * terribly complete, but it's probably good enough for + * EXPLAIN's purposes; especially since anything more would be + * either hopelessly confusing or an even poorer + * representation of what the plan is actually doing. + */ + need_parens = (list_length(fstore->newvals) != 1); + if (need_parens) + appendStringInfoString(buf, "ROW("); + get_rule_expr((Node *) fstore->newvals, context, showimplicit); + if (need_parens) + appendStringInfoChar(buf, ')'); + } + break; + + case T_RelabelType: + { + RelabelType *relabel = (RelabelType *) node; + Node *arg = (Node *) relabel->arg; + + if (relabel->relabelformat == COERCE_IMPLICIT_CAST && + !showimplicit) + { + /* don't show the implicit cast */ + get_rule_expr_paren(arg, context, false, node); + } + else + { + get_coercion_expr(arg, context, + relabel->resulttype, + relabel->resulttypmod, + node); + } + } + break; + + case T_CoerceViaIO: + { + CoerceViaIO *iocoerce = (CoerceViaIO *) node; + Node *arg = (Node *) iocoerce->arg; + + if (iocoerce->coerceformat == COERCE_IMPLICIT_CAST && + !showimplicit) + { + /* don't show the implicit cast */ + get_rule_expr_paren(arg, context, false, node); + } + else + { + get_coercion_expr(arg, context, + iocoerce->resulttype, + -1, + node); + } + } + break; + + case T_ArrayCoerceExpr: + { + ArrayCoerceExpr *acoerce = (ArrayCoerceExpr *) node; + Node *arg = (Node *) acoerce->arg; + + if (acoerce->coerceformat == COERCE_IMPLICIT_CAST && + !showimplicit) + { + /* don't show the implicit cast */ + get_rule_expr_paren(arg, context, false, node); + } + else + { + get_coercion_expr(arg, context, + acoerce->resulttype, + acoerce->resulttypmod, + node); + } + } + break; + + case T_ConvertRowtypeExpr: + { + ConvertRowtypeExpr *convert = (ConvertRowtypeExpr *) node; + Node *arg = (Node *) convert->arg; + + if (convert->convertformat == COERCE_IMPLICIT_CAST && + !showimplicit) + { + /* don't show the implicit cast */ + get_rule_expr_paren(arg, context, false, node); + } + else + { + get_coercion_expr(arg, context, + convert->resulttype, -1, + node); + } + } + break; + + case T_CollateExpr: + { + CollateExpr *collate = (CollateExpr *) node; + Node *arg = (Node *) collate->arg; + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(arg, context, showimplicit, node); + appendStringInfo(buf, " COLLATE %s", + generate_collation_name(collate->collOid)); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + break; + + case T_CaseExpr: + { + CaseExpr *caseexpr = (CaseExpr *) node; + ListCell *temp; + + appendContextKeyword(context, "CASE", + 0, PRETTYINDENT_VAR, 0); + if (caseexpr->arg) + { + appendStringInfoChar(buf, ' '); + get_rule_expr((Node *) caseexpr->arg, context, true); + } + foreach(temp, caseexpr->args) + { + CaseWhen *when = (CaseWhen *) lfirst(temp); + Node *w = (Node *) when->expr; + + if (caseexpr->arg) + { + /* + * The parser should have produced WHEN clauses of the + * form "CaseTestExpr = RHS", possibly with an + * implicit coercion inserted above the CaseTestExpr. + * For accurate decompilation of rules it's essential + * that we show just the RHS. However in an + * expression that's been through the optimizer, the + * WHEN clause could be almost anything (since the + * equality operator could have been expanded into an + * inline function). If we don't recognize the form + * of the WHEN clause, just punt and display it as-is. + */ + if (IsA(w, OpExpr)) + { + List *args = ((OpExpr *) w)->args; + + if (list_length(args) == 2 && + IsA(strip_implicit_coercions(linitial(args)), + CaseTestExpr)) + w = (Node *) lsecond(args); + } + } + + if (!PRETTY_INDENT(context)) + appendStringInfoChar(buf, ' '); + appendContextKeyword(context, "WHEN ", + 0, 0, 0); + get_rule_expr(w, context, false); + appendStringInfoString(buf, " THEN "); + get_rule_expr((Node *) when->result, context, true); + } + if (!PRETTY_INDENT(context)) + appendStringInfoChar(buf, ' '); + appendContextKeyword(context, "ELSE ", + 0, 0, 0); + get_rule_expr((Node *) caseexpr->defresult, context, true); + if (!PRETTY_INDENT(context)) + appendStringInfoChar(buf, ' '); + appendContextKeyword(context, "END", + -PRETTYINDENT_VAR, 0, 0); + } + break; + + case T_CaseTestExpr: + { + /* + * Normally we should never get here, since for expressions + * that can contain this node type we attempt to avoid + * recursing to it. But in an optimized expression we might + * be unable to avoid that (see comments for CaseExpr). If we + * do see one, print it as CASE_TEST_EXPR. + */ + appendStringInfoString(buf, "CASE_TEST_EXPR"); + } + break; + + case T_ArrayExpr: + { + ArrayExpr *arrayexpr = (ArrayExpr *) node; + + appendStringInfoString(buf, "ARRAY["); + get_rule_expr((Node *) arrayexpr->elements, context, true); + appendStringInfoChar(buf, ']'); + + /* + * If the array isn't empty, we assume its elements are + * coerced to the desired type. If it's empty, though, we + * need an explicit coercion to the array type. + */ + if (arrayexpr->elements == NIL) + appendStringInfo(buf, "::%s", + format_type_with_typemod(arrayexpr->array_typeid, -1)); + } + break; + + case T_RowExpr: + { + RowExpr *rowexpr = (RowExpr *) node; + TupleDesc tupdesc = NULL; + ListCell *arg; + int i; + char *sep; + + /* + * If it's a named type and not RECORD, we may have to skip + * dropped columns and/or claim there are NULLs for added + * columns. + */ + if (rowexpr->row_typeid != RECORDOID) + { + tupdesc = lookup_rowtype_tupdesc(rowexpr->row_typeid, -1); + Assert(list_length(rowexpr->args) <= tupdesc->natts); + } + + /* + * SQL99 allows "ROW" to be omitted when there is more than + * one column, but for simplicity we always print it. + */ + appendStringInfoString(buf, "ROW("); + sep = ""; + i = 0; + foreach(arg, rowexpr->args) + { + Node *e = (Node *) lfirst(arg); + + if (tupdesc == NULL || + !TupleDescAttr(tupdesc, i)->attisdropped) + { + appendStringInfoString(buf, sep); + /* Whole-row Vars need special treatment here */ + get_rule_expr_toplevel(e, context, true); + sep = ", "; + } + i++; + } + if (tupdesc != NULL) + { + while (i < tupdesc->natts) + { + if (!TupleDescAttr(tupdesc, i)->attisdropped) + { + appendStringInfoString(buf, sep); + appendStringInfoString(buf, "NULL"); + sep = ", "; + } + i++; + } + + ReleaseTupleDesc(tupdesc); + } + appendStringInfoChar(buf, ')'); + if (rowexpr->row_format == COERCE_EXPLICIT_CAST) + appendStringInfo(buf, "::%s", + format_type_with_typemod(rowexpr->row_typeid, -1)); + } + break; + + case T_RowCompareExpr: + { + RowCompareExpr *rcexpr = (RowCompareExpr *) node; + + /* + * SQL99 allows "ROW" to be omitted when there is more than + * one column, but for simplicity we always print it. Within + * a ROW expression, whole-row Vars need special treatment, so + * use get_rule_list_toplevel. + */ + appendStringInfoString(buf, "(ROW("); + get_rule_list_toplevel(rcexpr->largs, context, true); + + /* + * We assume that the name of the first-column operator will + * do for all the rest too. This is definitely open to + * failure, eg if some but not all operators were renamed + * since the construct was parsed, but there seems no way to + * be perfect. + */ + appendStringInfo(buf, ") %s ROW(", + generate_operator_name(linitial_oid(rcexpr->opnos), + exprType(linitial(rcexpr->largs)), + exprType(linitial(rcexpr->rargs)))); + get_rule_list_toplevel(rcexpr->rargs, context, true); + appendStringInfoString(buf, "))"); + } + break; + + case T_CoalesceExpr: + { + CoalesceExpr *coalesceexpr = (CoalesceExpr *) node; + + appendStringInfoString(buf, "COALESCE("); + get_rule_expr((Node *) coalesceexpr->args, context, true); + appendStringInfoChar(buf, ')'); + } + break; + + case T_MinMaxExpr: + { + MinMaxExpr *minmaxexpr = (MinMaxExpr *) node; + + switch (minmaxexpr->op) + { + case IS_GREATEST: + appendStringInfoString(buf, "GREATEST("); + break; + case IS_LEAST: + appendStringInfoString(buf, "LEAST("); + break; + } + get_rule_expr((Node *) minmaxexpr->args, context, true); + appendStringInfoChar(buf, ')'); + } + break; + + case T_SQLValueFunction: + { + SQLValueFunction *svf = (SQLValueFunction *) node; + + /* + * Note: this code knows that typmod for time, timestamp, and + * timestamptz just prints as integer. + */ + switch (svf->op) + { + case SVFOP_CURRENT_DATE: + appendStringInfoString(buf, "CURRENT_DATE"); + break; + case SVFOP_CURRENT_TIME: + appendStringInfoString(buf, "CURRENT_TIME"); + break; + case SVFOP_CURRENT_TIME_N: + appendStringInfo(buf, "CURRENT_TIME(%d)", svf->typmod); + break; + case SVFOP_CURRENT_TIMESTAMP: + appendStringInfoString(buf, "CURRENT_TIMESTAMP"); + break; + case SVFOP_CURRENT_TIMESTAMP_N: + appendStringInfo(buf, "CURRENT_TIMESTAMP(%d)", + svf->typmod); + break; + case SVFOP_LOCALTIME: + appendStringInfoString(buf, "LOCALTIME"); + break; + case SVFOP_LOCALTIME_N: + appendStringInfo(buf, "LOCALTIME(%d)", svf->typmod); + break; + case SVFOP_LOCALTIMESTAMP: + appendStringInfoString(buf, "LOCALTIMESTAMP"); + break; + case SVFOP_LOCALTIMESTAMP_N: + appendStringInfo(buf, "LOCALTIMESTAMP(%d)", + svf->typmod); + break; + case SVFOP_CURRENT_ROLE: + appendStringInfoString(buf, "CURRENT_ROLE"); + break; + case SVFOP_CURRENT_USER: + appendStringInfoString(buf, "CURRENT_USER"); + break; + case SVFOP_USER: + appendStringInfoString(buf, "USER"); + break; + case SVFOP_SESSION_USER: + appendStringInfoString(buf, "SESSION_USER"); + break; + case SVFOP_CURRENT_CATALOG: + appendStringInfoString(buf, "CURRENT_CATALOG"); + break; + case SVFOP_CURRENT_SCHEMA: + appendStringInfoString(buf, "CURRENT_SCHEMA"); + break; + } + } + break; + + case T_XmlExpr: + { + XmlExpr *xexpr = (XmlExpr *) node; + bool needcomma = false; + ListCell *arg; + ListCell *narg; + Const *con; + + switch (xexpr->op) + { + case IS_XMLCONCAT: + appendStringInfoString(buf, "XMLCONCAT("); + break; + case IS_XMLELEMENT: + appendStringInfoString(buf, "XMLELEMENT("); + break; + case IS_XMLFOREST: + appendStringInfoString(buf, "XMLFOREST("); + break; + case IS_XMLPARSE: + appendStringInfoString(buf, "XMLPARSE("); + break; + case IS_XMLPI: + appendStringInfoString(buf, "XMLPI("); + break; + case IS_XMLROOT: + appendStringInfoString(buf, "XMLROOT("); + break; + case IS_XMLSERIALIZE: + appendStringInfoString(buf, "XMLSERIALIZE("); + break; + case IS_DOCUMENT: + break; + } + if (xexpr->op == IS_XMLPARSE || xexpr->op == IS_XMLSERIALIZE) + { + if (xexpr->xmloption == XMLOPTION_DOCUMENT) + appendStringInfoString(buf, "DOCUMENT "); + else + appendStringInfoString(buf, "CONTENT "); + } + if (xexpr->name) + { + appendStringInfo(buf, "NAME %s", + quote_identifier(map_xml_name_to_sql_identifier(xexpr->name))); + needcomma = true; + } + if (xexpr->named_args) + { + if (xexpr->op != IS_XMLFOREST) + { + if (needcomma) + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, "XMLATTRIBUTES("); + needcomma = false; + } + forboth(arg, xexpr->named_args, narg, xexpr->arg_names) + { + Node *e = (Node *) lfirst(arg); + char *argname = strVal(lfirst(narg)); + + if (needcomma) + appendStringInfoString(buf, ", "); + get_rule_expr((Node *) e, context, true); + appendStringInfo(buf, " AS %s", + quote_identifier(map_xml_name_to_sql_identifier(argname))); + needcomma = true; + } + if (xexpr->op != IS_XMLFOREST) + appendStringInfoChar(buf, ')'); + } + if (xexpr->args) + { + if (needcomma) + appendStringInfoString(buf, ", "); + switch (xexpr->op) + { + case IS_XMLCONCAT: + case IS_XMLELEMENT: + case IS_XMLFOREST: + case IS_XMLPI: + case IS_XMLSERIALIZE: + /* no extra decoration needed */ + get_rule_expr((Node *) xexpr->args, context, true); + break; + case IS_XMLPARSE: + Assert(list_length(xexpr->args) == 2); + + get_rule_expr((Node *) linitial(xexpr->args), + context, true); + + con = lsecond_node(Const, xexpr->args); + Assert(!con->constisnull); + if (DatumGetBool(con->constvalue)) + appendStringInfoString(buf, + " PRESERVE WHITESPACE"); + else + appendStringInfoString(buf, + " STRIP WHITESPACE"); + break; + case IS_XMLROOT: + Assert(list_length(xexpr->args) == 3); + + get_rule_expr((Node *) linitial(xexpr->args), + context, true); + + appendStringInfoString(buf, ", VERSION "); + con = (Const *) lsecond(xexpr->args); + if (IsA(con, Const) && + con->constisnull) + appendStringInfoString(buf, "NO VALUE"); + else + get_rule_expr((Node *) con, context, false); + + con = lthird_node(Const, xexpr->args); + if (con->constisnull) + /* suppress STANDALONE NO VALUE */ ; + else + { + switch (DatumGetInt32(con->constvalue)) + { + case XML_STANDALONE_YES: + appendStringInfoString(buf, + ", STANDALONE YES"); + break; + case XML_STANDALONE_NO: + appendStringInfoString(buf, + ", STANDALONE NO"); + break; + case XML_STANDALONE_NO_VALUE: + appendStringInfoString(buf, + ", STANDALONE NO VALUE"); + break; + default: + break; + } + } + break; + case IS_DOCUMENT: + get_rule_expr_paren((Node *) xexpr->args, context, false, node); + break; + } + + } + if (xexpr->op == IS_XMLSERIALIZE) + appendStringInfo(buf, " AS %s", + format_type_with_typemod(xexpr->type, + xexpr->typmod)); + if (xexpr->op == IS_DOCUMENT) + appendStringInfoString(buf, " IS DOCUMENT"); + else + appendStringInfoChar(buf, ')'); + } + break; + + case T_NullTest: + { + NullTest *ntest = (NullTest *) node; + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren((Node *) ntest->arg, context, true, node); + + /* + * For scalar inputs, we prefer to print as IS [NOT] NULL, + * which is shorter and traditional. If it's a rowtype input + * but we're applying a scalar test, must print IS [NOT] + * DISTINCT FROM NULL to be semantically correct. + */ + if (ntest->argisrow || + !type_is_rowtype(exprType((Node *) ntest->arg))) + { + switch (ntest->nulltesttype) + { + case IS_NULL: + appendStringInfoString(buf, " IS NULL"); + break; + case IS_NOT_NULL: + appendStringInfoString(buf, " IS NOT NULL"); + break; + default: + elog(ERROR, "unrecognized nulltesttype: %d", + (int) ntest->nulltesttype); + } + } + else + { + switch (ntest->nulltesttype) + { + case IS_NULL: + appendStringInfoString(buf, " IS NOT DISTINCT FROM NULL"); + break; + case IS_NOT_NULL: + appendStringInfoString(buf, " IS DISTINCT FROM NULL"); + break; + default: + elog(ERROR, "unrecognized nulltesttype: %d", + (int) ntest->nulltesttype); + } + } + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + break; + + case T_BooleanTest: + { + BooleanTest *btest = (BooleanTest *) node; + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren((Node *) btest->arg, context, false, node); + switch (btest->booltesttype) + { + case IS_TRUE: + appendStringInfoString(buf, " IS TRUE"); + break; + case IS_NOT_TRUE: + appendStringInfoString(buf, " IS NOT TRUE"); + break; + case IS_FALSE: + appendStringInfoString(buf, " IS FALSE"); + break; + case IS_NOT_FALSE: + appendStringInfoString(buf, " IS NOT FALSE"); + break; + case IS_UNKNOWN: + appendStringInfoString(buf, " IS UNKNOWN"); + break; + case IS_NOT_UNKNOWN: + appendStringInfoString(buf, " IS NOT UNKNOWN"); + break; + default: + elog(ERROR, "unrecognized booltesttype: %d", + (int) btest->booltesttype); + } + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + break; + + case T_CoerceToDomain: + { + CoerceToDomain *ctest = (CoerceToDomain *) node; + Node *arg = (Node *) ctest->arg; + + if (ctest->coercionformat == COERCE_IMPLICIT_CAST && + !showimplicit) + { + /* don't show the implicit cast */ + get_rule_expr(arg, context, false); + } + else + { + get_coercion_expr(arg, context, + ctest->resulttype, + ctest->resulttypmod, + node); + } + } + break; + + case T_CoerceToDomainValue: + appendStringInfoString(buf, "VALUE"); + break; + + case T_SetToDefault: + appendStringInfoString(buf, "DEFAULT"); + break; + + case T_CurrentOfExpr: + { + CurrentOfExpr *cexpr = (CurrentOfExpr *) node; + + if (cexpr->cursor_name) + appendStringInfo(buf, "CURRENT OF %s", + quote_identifier(cexpr->cursor_name)); + else + appendStringInfo(buf, "CURRENT OF $%d", + cexpr->cursor_param); + } + break; + + case T_NextValueExpr: + { + NextValueExpr *nvexpr = (NextValueExpr *) node; + + /* + * This isn't exactly nextval(), but that seems close enough + * for EXPLAIN's purposes. + */ + appendStringInfoString(buf, "nextval("); + simple_quote_literal(buf, + generate_relation_name(nvexpr->seqid, + NIL)); + appendStringInfoChar(buf, ')'); + } + break; + + case T_InferenceElem: + { + InferenceElem *iexpr = (InferenceElem *) node; + bool save_varprefix; + bool need_parens; + + /* + * InferenceElem can only refer to target relation, so a + * prefix is not useful, and indeed would cause parse errors. + */ + save_varprefix = context->varprefix; + context->varprefix = false; + + /* + * Parenthesize the element unless it's a simple Var or a bare + * function call. Follows pg_get_indexdef_worker(). + */ + need_parens = !IsA(iexpr->expr, Var); + if (IsA(iexpr->expr, FuncExpr) && + ((FuncExpr *) iexpr->expr)->funcformat == + COERCE_EXPLICIT_CALL) + need_parens = false; + + if (need_parens) + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) iexpr->expr, + context, false); + if (need_parens) + appendStringInfoChar(buf, ')'); + + context->varprefix = save_varprefix; + + if (iexpr->infercollid) + appendStringInfo(buf, " COLLATE %s", + generate_collation_name(iexpr->infercollid)); + + /* Add the operator class name, if not default */ + if (iexpr->inferopclass) + { + Oid inferopclass = iexpr->inferopclass; + Oid inferopcinputtype = get_opclass_input_type(iexpr->inferopclass); + + get_opclass_name(inferopclass, inferopcinputtype, buf); + } + } + break; + + case T_PartitionBoundSpec: + { + PartitionBoundSpec *spec = (PartitionBoundSpec *) node; + ListCell *cell; + char *sep; + + if (spec->is_default) + { + appendStringInfoString(buf, "DEFAULT"); + break; + } + + switch (spec->strategy) + { + case PARTITION_STRATEGY_HASH: + Assert(spec->modulus > 0 && spec->remainder >= 0); + Assert(spec->modulus > spec->remainder); + + appendStringInfoString(buf, "FOR VALUES"); + appendStringInfo(buf, " WITH (modulus %d, remainder %d)", + spec->modulus, spec->remainder); + break; + + case PARTITION_STRATEGY_LIST: + Assert(spec->listdatums != NIL); + + appendStringInfoString(buf, "FOR VALUES IN ("); + sep = ""; + foreach(cell, spec->listdatums) + { + Const *val = castNode(Const, lfirst(cell)); + + appendStringInfoString(buf, sep); + get_const_expr(val, context, -1); + sep = ", "; + } + + appendStringInfoChar(buf, ')'); + break; + + case PARTITION_STRATEGY_RANGE: + Assert(spec->lowerdatums != NIL && + spec->upperdatums != NIL && + list_length(spec->lowerdatums) == + list_length(spec->upperdatums)); + + appendStringInfo(buf, "FOR VALUES FROM %s TO %s", + get_range_partbound_string(spec->lowerdatums), + get_range_partbound_string(spec->upperdatums)); + break; + + default: + elog(ERROR, "unrecognized partition strategy: %d", + (int) spec->strategy); + break; + } + } + break; + + case T_List: + { + char *sep; + ListCell *l; + + sep = ""; + foreach(l, (List *) node) + { + appendStringInfoString(buf, sep); + get_rule_expr((Node *) lfirst(l), context, showimplicit); + sep = ", "; + } + } + break; + + case T_TableFunc: + get_tablefunc((TableFunc *) node, context, showimplicit); + break; + + default: + elog(ERROR, "unrecognized node type: %d", (int) nodeTag(node)); + break; + } +} + +/* + * get_rule_expr_toplevel - Parse back a toplevel expression + * + * Same as get_rule_expr(), except that if the expr is just a Var, we pass + * istoplevel = true not false to get_variable(). This causes whole-row Vars + * to get printed with decoration that will prevent expansion of "*". + * We need to use this in contexts such as ROW() and VALUES(), where the + * parser would expand "foo.*" appearing at top level. (In principle we'd + * use this in get_target_list() too, but that has additional worries about + * whether to print AS, so it needs to invoke get_variable() directly anyway.) + */ +static void +get_rule_expr_toplevel(Node *node, deparse_context *context, + bool showimplicit) +{ + if (node && IsA(node, Var)) + (void) get_variable((Var *) node, 0, true, context); + else + get_rule_expr(node, context, showimplicit); +} + +/* + * get_rule_list_toplevel - Parse back a list of toplevel expressions + * + * Apply get_rule_expr_toplevel() to each element of a List. + * + * This adds commas between the expressions, but caller is responsible + * for printing surrounding decoration. + */ +static void +get_rule_list_toplevel(List *lst, deparse_context *context, + bool showimplicit) +{ + const char *sep; + ListCell *lc; + + sep = ""; + foreach(lc, lst) + { + Node *e = (Node *) lfirst(lc); + + appendStringInfoString(context->buf, sep); + get_rule_expr_toplevel(e, context, showimplicit); + sep = ", "; + } +} + +/* + * get_rule_expr_funccall - Parse back a function-call expression + * + * Same as get_rule_expr(), except that we guarantee that the output will + * look like a function call, or like one of the things the grammar treats as + * equivalent to a function call (see the func_expr_windowless production). + * This is needed in places where the grammar uses func_expr_windowless and + * you can't substitute a parenthesized a_expr. If what we have isn't going + * to look like a function call, wrap it in a dummy CAST() expression, which + * will satisfy the grammar --- and, indeed, is likely what the user wrote to + * produce such a thing. + */ +static void +get_rule_expr_funccall(Node *node, deparse_context *context, + bool showimplicit) +{ + if (looks_like_function(node)) + get_rule_expr(node, context, showimplicit); + else + { + StringInfo buf = context->buf; + + appendStringInfoString(buf, "CAST("); + /* no point in showing any top-level implicit cast */ + get_rule_expr(node, context, false); + appendStringInfo(buf, " AS %s)", + format_type_with_typemod(exprType(node), + exprTypmod(node))); + } +} + +/* + * Helper function to identify node types that satisfy func_expr_windowless. + * If in doubt, "false" is always a safe answer. + */ +static bool +looks_like_function(Node *node) +{ + if (node == NULL) + return false; /* probably shouldn't happen */ + switch (nodeTag(node)) + { + case T_FuncExpr: + /* OK, unless it's going to deparse as a cast */ + return (((FuncExpr *) node)->funcformat == COERCE_EXPLICIT_CALL || + ((FuncExpr *) node)->funcformat == COERCE_SQL_SYNTAX); + case T_NullIfExpr: + case T_CoalesceExpr: + case T_MinMaxExpr: + case T_SQLValueFunction: + case T_XmlExpr: + /* these are all accepted by func_expr_common_subexpr */ + return true; + default: + break; + } + return false; +} + + +/* + * get_oper_expr - Parse back an OpExpr node + */ +static void +get_oper_expr(OpExpr *expr, deparse_context *context) +{ + StringInfo buf = context->buf; + Oid opno = expr->opno; + List *args = expr->args; + + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + if (list_length(args) == 2) + { + /* binary operator */ + Node *arg1 = (Node *) linitial(args); + Node *arg2 = (Node *) lsecond(args); + + get_rule_expr_paren(arg1, context, true, (Node *) expr); + appendStringInfo(buf, " %s ", + generate_operator_name(opno, + exprType(arg1), + exprType(arg2))); + get_rule_expr_paren(arg2, context, true, (Node *) expr); + } + else + { + /* prefix operator */ + Node *arg = (Node *) linitial(args); + + appendStringInfo(buf, "%s ", + generate_operator_name(opno, + InvalidOid, + exprType(arg))); + get_rule_expr_paren(arg, context, true, (Node *) expr); + } + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); +} + +/* + * get_func_expr - Parse back a FuncExpr node + */ +static void +get_func_expr(FuncExpr *expr, deparse_context *context, + bool showimplicit) +{ + StringInfo buf = context->buf; + Oid funcoid = expr->funcid; + Oid argtypes[FUNC_MAX_ARGS]; + int nargs; + List *argnames; + bool use_variadic; + ListCell *l; + + /* + * If the function call came from an implicit coercion, then just show the + * first argument --- unless caller wants to see implicit coercions. + */ + if (expr->funcformat == COERCE_IMPLICIT_CAST && !showimplicit) + { + get_rule_expr_paren((Node *) linitial(expr->args), context, + false, (Node *) expr); + return; + } + + /* + * If the function call came from a cast, then show the first argument + * plus an explicit cast operation. + */ + if (expr->funcformat == COERCE_EXPLICIT_CAST || + expr->funcformat == COERCE_IMPLICIT_CAST) + { + Node *arg = linitial(expr->args); + Oid rettype = expr->funcresulttype; + int32 coercedTypmod; + + /* Get the typmod if this is a length-coercion function */ + (void) exprIsLengthCoercion((Node *) expr, &coercedTypmod); + + get_coercion_expr(arg, context, + rettype, coercedTypmod, + (Node *) expr); + + return; + } + + /* + * If the function was called using one of the SQL spec's random special + * syntaxes, try to reproduce that. If we don't recognize the function, + * fall through. + */ + if (expr->funcformat == COERCE_SQL_SYNTAX) + { + if (get_func_sql_syntax(expr, context)) + return; + } + + /* + * Normal function: display as proname(args). First we need to extract + * the argument datatypes. + */ + if (list_length(expr->args) > FUNC_MAX_ARGS) + ereport(ERROR, + (errcode(ERRCODE_TOO_MANY_ARGUMENTS), + errmsg("too many arguments"))); + nargs = 0; + argnames = NIL; + foreach(l, expr->args) + { + Node *arg = (Node *) lfirst(l); + + if (IsA(arg, NamedArgExpr)) + argnames = lappend(argnames, ((NamedArgExpr *) arg)->name); + argtypes[nargs] = exprType(arg); + nargs++; + } + + appendStringInfo(buf, "%s(", + generate_function_name(funcoid, nargs, + argnames, argtypes, + expr->funcvariadic, + &use_variadic, + context->special_exprkind)); + nargs = 0; + foreach(l, expr->args) + { + if (nargs++ > 0) + appendStringInfoString(buf, ", "); + if (use_variadic && lnext(expr->args, l) == NULL) + appendStringInfoString(buf, "VARIADIC "); + get_rule_expr((Node *) lfirst(l), context, true); + } + appendStringInfoChar(buf, ')'); +} + +/* + * get_agg_expr - Parse back an Aggref node + */ +static void +get_agg_expr(Aggref *aggref, deparse_context *context, + Aggref *original_aggref) +{ + StringInfo buf = context->buf; + Oid argtypes[FUNC_MAX_ARGS]; + int nargs; + bool use_variadic; + + /* + * For a combining aggregate, we look up and deparse the corresponding + * partial aggregate instead. This is necessary because our input + * argument list has been replaced; the new argument list always has just + * one element, which will point to a partial Aggref that supplies us with + * transition states to combine. + */ + if (DO_AGGSPLIT_COMBINE(aggref->aggsplit)) + { + TargetEntry *tle; + + Assert(list_length(aggref->args) == 1); + tle = linitial_node(TargetEntry, aggref->args); + resolve_special_varno((Node *) tle->expr, context, + get_agg_combine_expr, original_aggref); + return; + } + + /* + * Mark as PARTIAL, if appropriate. We look to the original aggref so as + * to avoid printing this when recursing from the code just above. + */ + if (DO_AGGSPLIT_SKIPFINAL(original_aggref->aggsplit)) + appendStringInfoString(buf, "PARTIAL "); + + /* Extract the argument types as seen by the parser */ + nargs = get_aggregate_argtypes(aggref, argtypes); + + /* Print the aggregate name, schema-qualified if needed */ + appendStringInfo(buf, "%s(%s", + generate_function_name(aggref->aggfnoid, nargs, + NIL, argtypes, + aggref->aggvariadic, + &use_variadic, + context->special_exprkind), + (aggref->aggdistinct != NIL) ? "DISTINCT " : ""); + + if (AGGKIND_IS_ORDERED_SET(aggref->aggkind)) + { + /* + * Ordered-set aggregates do not use "*" syntax. Also, we needn't + * worry about inserting VARIADIC. So we can just dump the direct + * args as-is. + */ + Assert(!aggref->aggvariadic); + get_rule_expr((Node *) aggref->aggdirectargs, context, true); + Assert(aggref->aggorder != NIL); + appendStringInfoString(buf, ") WITHIN GROUP (ORDER BY "); + get_rule_orderby(aggref->aggorder, aggref->args, false, context); + } + else + { + /* aggstar can be set only in zero-argument aggregates */ + if (aggref->aggstar) + appendStringInfoChar(buf, '*'); + else + { + ListCell *l; + int i; + + i = 0; + foreach(l, aggref->args) + { + TargetEntry *tle = (TargetEntry *) lfirst(l); + Node *arg = (Node *) tle->expr; + + Assert(!IsA(arg, NamedArgExpr)); + if (tle->resjunk) + continue; + if (i++ > 0) + appendStringInfoString(buf, ", "); + if (use_variadic && i == nargs) + appendStringInfoString(buf, "VARIADIC "); + get_rule_expr(arg, context, true); + } + } + + if (aggref->aggorder != NIL) + { + appendStringInfoString(buf, " ORDER BY "); + get_rule_orderby(aggref->aggorder, aggref->args, false, context); + } + } + + if (aggref->aggfilter != NULL) + { + appendStringInfoString(buf, ") FILTER (WHERE "); + get_rule_expr((Node *) aggref->aggfilter, context, false); + } + + appendStringInfoChar(buf, ')'); +} + +/* + * This is a helper function for get_agg_expr(). It's used when we deparse + * a combining Aggref; resolve_special_varno locates the corresponding partial + * Aggref and then calls this. + */ +static void +get_agg_combine_expr(Node *node, deparse_context *context, void *callback_arg) +{ + Aggref *aggref; + Aggref *original_aggref = callback_arg; + + if (!IsA(node, Aggref)) + elog(ERROR, "combining Aggref does not point to an Aggref"); + + aggref = (Aggref *) node; + get_agg_expr(aggref, context, original_aggref); +} + +/* + * get_windowfunc_expr - Parse back a WindowFunc node + */ +static void +get_windowfunc_expr(WindowFunc *wfunc, deparse_context *context) +{ + StringInfo buf = context->buf; + Oid argtypes[FUNC_MAX_ARGS]; + int nargs; + List *argnames; + ListCell *l; + + if (list_length(wfunc->args) > FUNC_MAX_ARGS) + ereport(ERROR, + (errcode(ERRCODE_TOO_MANY_ARGUMENTS), + errmsg("too many arguments"))); + nargs = 0; + argnames = NIL; + foreach(l, wfunc->args) + { + Node *arg = (Node *) lfirst(l); + + if (IsA(arg, NamedArgExpr)) + argnames = lappend(argnames, ((NamedArgExpr *) arg)->name); + argtypes[nargs] = exprType(arg); + nargs++; + } + + appendStringInfo(buf, "%s(", + generate_function_name(wfunc->winfnoid, nargs, + argnames, argtypes, + false, NULL, + context->special_exprkind)); + /* winstar can be set only in zero-argument aggregates */ + if (wfunc->winstar) + appendStringInfoChar(buf, '*'); + else + get_rule_expr((Node *) wfunc->args, context, true); + + if (wfunc->aggfilter != NULL) + { + appendStringInfoString(buf, ") FILTER (WHERE "); + get_rule_expr((Node *) wfunc->aggfilter, context, false); + } + + appendStringInfoString(buf, ") OVER "); + + foreach(l, context->windowClause) + { + WindowClause *wc = (WindowClause *) lfirst(l); + + if (wc->winref == wfunc->winref) + { + if (wc->name) + appendStringInfoString(buf, quote_identifier(wc->name)); + else + get_rule_windowspec(wc, context->windowTList, context); + break; + } + } + if (l == NULL) + { + if (context->windowClause) + elog(ERROR, "could not find window clause for winref %u", + wfunc->winref); + + /* + * In EXPLAIN, we don't have window context information available, so + * we have to settle for this: + */ + appendStringInfoString(buf, "(?)"); + } +} + +/* + * get_func_sql_syntax - Parse back a SQL-syntax function call + * + * Returns true if we successfully deparsed, false if we did not + * recognize the function. + */ +static bool +get_func_sql_syntax(FuncExpr *expr, deparse_context *context) +{ + StringInfo buf = context->buf; + Oid funcoid = expr->funcid; + + switch (funcoid) + { + case F_TIMEZONE_INTERVAL_TIMESTAMP: + case F_TIMEZONE_INTERVAL_TIMESTAMPTZ: + case F_TIMEZONE_INTERVAL_TIMETZ: + case F_TIMEZONE_TEXT_TIMESTAMP: + case F_TIMEZONE_TEXT_TIMESTAMPTZ: + case F_TIMEZONE_TEXT_TIMETZ: + /* AT TIME ZONE ... note reversed argument order */ + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, " AT TIME ZONE "); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_OVERLAPS_TIMESTAMPTZ_INTERVAL_TIMESTAMPTZ_INTERVAL: + case F_OVERLAPS_TIMESTAMPTZ_INTERVAL_TIMESTAMPTZ_TIMESTAMPTZ: + case F_OVERLAPS_TIMESTAMPTZ_TIMESTAMPTZ_TIMESTAMPTZ_INTERVAL: + case F_OVERLAPS_TIMESTAMPTZ_TIMESTAMPTZ_TIMESTAMPTZ_TIMESTAMPTZ: + case F_OVERLAPS_TIMESTAMP_INTERVAL_TIMESTAMP_INTERVAL: + case F_OVERLAPS_TIMESTAMP_INTERVAL_TIMESTAMP_TIMESTAMP: + case F_OVERLAPS_TIMESTAMP_TIMESTAMP_TIMESTAMP_INTERVAL: + case F_OVERLAPS_TIMESTAMP_TIMESTAMP_TIMESTAMP_TIMESTAMP: + case F_OVERLAPS_TIMETZ_TIMETZ_TIMETZ_TIMETZ: + case F_OVERLAPS_TIME_INTERVAL_TIME_INTERVAL: + case F_OVERLAPS_TIME_INTERVAL_TIME_TIME: + case F_OVERLAPS_TIME_TIME_TIME_INTERVAL: + case F_OVERLAPS_TIME_TIME_TIME_TIME: + /* (x1, x2) OVERLAPS (y1, y2) */ + appendStringInfoString(buf, "(("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, ", "); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, ") OVERLAPS ("); + get_rule_expr((Node *) lthird(expr->args), context, false); + appendStringInfoString(buf, ", "); + get_rule_expr((Node *) lfourth(expr->args), context, false); + appendStringInfoString(buf, "))"); + return true; + + case F_EXTRACT_TEXT_DATE: + case F_EXTRACT_TEXT_TIME: + case F_EXTRACT_TEXT_TIMETZ: + case F_EXTRACT_TEXT_TIMESTAMP: + case F_EXTRACT_TEXT_TIMESTAMPTZ: + case F_EXTRACT_TEXT_INTERVAL: + /* EXTRACT (x FROM y) */ + appendStringInfoString(buf, "EXTRACT("); + { + Const *con = (Const *) linitial(expr->args); + + Assert(IsA(con, Const) && + con->consttype == TEXTOID && + !con->constisnull); + appendStringInfoString(buf, TextDatumGetCString(con->constvalue)); + } + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_IS_NORMALIZED: + /* IS xxx NORMALIZED */ + appendStringInfoString(buf, "(("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, ") IS"); + if (list_length(expr->args) == 2) + { + Const *con = (Const *) lsecond(expr->args); + + Assert(IsA(con, Const) && + con->consttype == TEXTOID && + !con->constisnull); + appendStringInfo(buf, " %s", + TextDatumGetCString(con->constvalue)); + } + appendStringInfoString(buf, " NORMALIZED)"); + return true; + + case F_PG_COLLATION_FOR: + /* COLLATION FOR */ + appendStringInfoString(buf, "COLLATION FOR ("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + /* + * XXX EXTRACT, a/k/a date_part(), is intentionally not covered + * yet. Add it after we change the return type to numeric. + */ + + case F_NORMALIZE: + /* NORMALIZE() */ + appendStringInfoString(buf, "NORMALIZE("); + get_rule_expr((Node *) linitial(expr->args), context, false); + if (list_length(expr->args) == 2) + { + Const *con = (Const *) lsecond(expr->args); + + Assert(IsA(con, Const) && + con->consttype == TEXTOID && + !con->constisnull); + appendStringInfo(buf, ", %s", + TextDatumGetCString(con->constvalue)); + } + appendStringInfoChar(buf, ')'); + return true; + + case F_OVERLAY_BIT_BIT_INT4: + case F_OVERLAY_BIT_BIT_INT4_INT4: + case F_OVERLAY_BYTEA_BYTEA_INT4: + case F_OVERLAY_BYTEA_BYTEA_INT4_INT4: + case F_OVERLAY_TEXT_TEXT_INT4: + case F_OVERLAY_TEXT_TEXT_INT4_INT4: + /* OVERLAY() */ + appendStringInfoString(buf, "OVERLAY("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, " PLACING "); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) lthird(expr->args), context, false); + if (list_length(expr->args) == 4) + { + appendStringInfoString(buf, " FOR "); + get_rule_expr((Node *) lfourth(expr->args), context, false); + } + appendStringInfoChar(buf, ')'); + return true; + + case F_POSITION_BIT_BIT: + case F_POSITION_BYTEA_BYTEA: + case F_POSITION_TEXT_TEXT: + /* POSITION() ... extra parens since args are b_expr not a_expr */ + appendStringInfoString(buf, "POSITION(("); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, ") IN ("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, "))"); + return true; + + case F_SUBSTRING_BIT_INT4: + case F_SUBSTRING_BIT_INT4_INT4: + case F_SUBSTRING_BYTEA_INT4: + case F_SUBSTRING_BYTEA_INT4_INT4: + case F_SUBSTRING_TEXT_INT4: + case F_SUBSTRING_TEXT_INT4_INT4: + /* SUBSTRING FROM/FOR (i.e., integer-position variants) */ + appendStringInfoString(buf, "SUBSTRING("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) lsecond(expr->args), context, false); + if (list_length(expr->args) == 3) + { + appendStringInfoString(buf, " FOR "); + get_rule_expr((Node *) lthird(expr->args), context, false); + } + appendStringInfoChar(buf, ')'); + return true; + + case F_SUBSTRING_TEXT_TEXT_TEXT: + /* SUBSTRING SIMILAR/ESCAPE */ + appendStringInfoString(buf, "SUBSTRING("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, " SIMILAR "); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, " ESCAPE "); + get_rule_expr((Node *) lthird(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_BTRIM_BYTEA_BYTEA: + case F_BTRIM_TEXT: + case F_BTRIM_TEXT_TEXT: + /* TRIM() */ + appendStringInfoString(buf, "TRIM(BOTH"); + if (list_length(expr->args) == 2) + { + appendStringInfoChar(buf, ' '); + get_rule_expr((Node *) lsecond(expr->args), context, false); + } + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_LTRIM_BYTEA_BYTEA: + case F_LTRIM_TEXT: + case F_LTRIM_TEXT_TEXT: + /* TRIM() */ + appendStringInfoString(buf, "TRIM(LEADING"); + if (list_length(expr->args) == 2) + { + appendStringInfoChar(buf, ' '); + get_rule_expr((Node *) lsecond(expr->args), context, false); + } + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_RTRIM_BYTEA_BYTEA: + case F_RTRIM_TEXT: + case F_RTRIM_TEXT_TEXT: + /* TRIM() */ + appendStringInfoString(buf, "TRIM(TRAILING"); + if (list_length(expr->args) == 2) + { + appendStringInfoChar(buf, ' '); + get_rule_expr((Node *) lsecond(expr->args), context, false); + } + appendStringInfoString(buf, " FROM "); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoChar(buf, ')'); + return true; + + case F_XMLEXISTS: + /* XMLEXISTS ... extra parens because args are c_expr */ + appendStringInfoString(buf, "XMLEXISTS(("); + get_rule_expr((Node *) linitial(expr->args), context, false); + appendStringInfoString(buf, ") PASSING ("); + get_rule_expr((Node *) lsecond(expr->args), context, false); + appendStringInfoString(buf, "))"); + return true; + } + return false; +} + +/* ---------- + * get_coercion_expr + * + * Make a string representation of a value coerced to a specific type + * ---------- + */ +static void +get_coercion_expr(Node *arg, deparse_context *context, + Oid resulttype, int32 resulttypmod, + Node *parentNode) +{ + StringInfo buf = context->buf; + + /* + * Since parse_coerce.c doesn't immediately collapse application of + * length-coercion functions to constants, what we'll typically see in + * such cases is a Const with typmod -1 and a length-coercion function + * right above it. Avoid generating redundant output. However, beware of + * suppressing casts when the user actually wrote something like + * 'foo'::text::char(3). + * + * Note: it might seem that we are missing the possibility of needing to + * print a COLLATE clause for such a Const. However, a Const could only + * have nondefault collation in a post-constant-folding tree, in which the + * length coercion would have been folded too. See also the special + * handling of CollateExpr in coerce_to_target_type(): any collation + * marking will be above the coercion node, not below it. + */ + if (arg && IsA(arg, Const) && + ((Const *) arg)->consttype == resulttype && + ((Const *) arg)->consttypmod == -1) + { + /* Show the constant without normal ::typename decoration */ + get_const_expr((Const *) arg, context, -1); + } + else + { + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr_paren(arg, context, false, parentNode); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + + /* + * Never emit resulttype(arg) functional notation. A pg_proc entry could + * take precedence, and a resulttype in pg_temp would require schema + * qualification that format_type_with_typemod() would usually omit. We've + * standardized on arg::resulttype, but CAST(arg AS resulttype) notation + * would work fine. + */ + appendStringInfo(buf, "::%s", + format_type_with_typemod(resulttype, resulttypmod)); +} + +/* ---------- + * get_const_expr + * + * Make a string representation of a Const + * + * showtype can be -1 to never show "::typename" decoration, or +1 to always + * show it, or 0 to show it only if the constant wouldn't be assumed to be + * the right type by default. + * + * If the Const's collation isn't default for its type, show that too. + * We mustn't do this when showtype is -1 (since that means the caller will + * print "::typename", and we can't put a COLLATE clause in between). It's + * caller's responsibility that collation isn't missed in such cases. + * ---------- + */ +static void +get_const_expr(Const *constval, deparse_context *context, int showtype) +{ + StringInfo buf = context->buf; + Oid typoutput; + bool typIsVarlena; + char *extval; + bool needlabel = false; + + if (constval->constisnull) + { + /* + * Always label the type of a NULL constant to prevent misdecisions + * about type when reparsing. + */ + appendStringInfoString(buf, "NULL"); + if (showtype >= 0) + { + appendStringInfo(buf, "::%s", + format_type_with_typemod(constval->consttype, + constval->consttypmod)); + get_const_collation(constval, context); + } + return; + } + + getTypeOutputInfo(constval->consttype, + &typoutput, &typIsVarlena); + + extval = OidOutputFunctionCall(typoutput, constval->constvalue); + + switch (constval->consttype) + { + case INT4OID: + + /* + * INT4 can be printed without any decoration, unless it is + * negative; in that case print it as '-nnn'::integer to ensure + * that the output will re-parse as a constant, not as a constant + * plus operator. In most cases we could get away with printing + * (-nnn) instead, because of the way that gram.y handles negative + * literals; but that doesn't work for INT_MIN, and it doesn't + * seem that much prettier anyway. + */ + if (extval[0] != '-') + appendStringInfoString(buf, extval); + else + { + appendStringInfo(buf, "'%s'", extval); + needlabel = true; /* we must attach a cast */ + } + break; + + case NUMERICOID: + + /* + * NUMERIC can be printed without quotes if it looks like a float + * constant (not an integer, and not Infinity or NaN) and doesn't + * have a leading sign (for the same reason as for INT4). + */ + if (isdigit((unsigned char) extval[0]) && + strcspn(extval, "eE.") != strlen(extval)) + { + appendStringInfoString(buf, extval); + } + else + { + appendStringInfo(buf, "'%s'", extval); + needlabel = true; /* we must attach a cast */ + } + break; + + case BOOLOID: + if (strcmp(extval, "t") == 0) + appendStringInfoString(buf, "true"); + else + appendStringInfoString(buf, "false"); + break; + + default: + simple_quote_literal(buf, extval); + break; + } + + pfree(extval); + + if (showtype < 0) + return; + + /* + * For showtype == 0, append ::typename unless the constant will be + * implicitly typed as the right type when it is read in. + * + * XXX this code has to be kept in sync with the behavior of the parser, + * especially make_const. + */ + switch (constval->consttype) + { + case BOOLOID: + case UNKNOWNOID: + /* These types can be left unlabeled */ + needlabel = false; + break; + case INT4OID: + /* We determined above whether a label is needed */ + break; + case NUMERICOID: + + /* + * Float-looking constants will be typed as numeric, which we + * checked above; but if there's a nondefault typmod we need to + * show it. + */ + needlabel |= (constval->consttypmod >= 0); + break; + default: + needlabel = true; + break; + } + if (needlabel || showtype > 0) + appendStringInfo(buf, "::%s", + format_type_with_typemod(constval->consttype, + constval->consttypmod)); + + get_const_collation(constval, context); +} + +/* + * helper for get_const_expr: append COLLATE if needed + */ +static void +get_const_collation(Const *constval, deparse_context *context) +{ + StringInfo buf = context->buf; + + if (OidIsValid(constval->constcollid)) + { + Oid typcollation = get_typcollation(constval->consttype); + + if (constval->constcollid != typcollation) + { + appendStringInfo(buf, " COLLATE %s", + generate_collation_name(constval->constcollid)); + } + } +} + +/* + * simple_quote_literal - Format a string as a SQL literal, append to buf + */ +static void +simple_quote_literal(StringInfo buf, const char *val) +{ + const char *valptr; + + /* + * We form the string literal according to the prevailing setting of + * standard_conforming_strings; we never use E''. User is responsible for + * making sure result is used correctly. + */ + appendStringInfoChar(buf, '\''); + for (valptr = val; *valptr; valptr++) + { + char ch = *valptr; + + if (SQL_STR_DOUBLE(ch, !standard_conforming_strings)) + appendStringInfoChar(buf, ch); + appendStringInfoChar(buf, ch); + } + appendStringInfoChar(buf, '\''); +} + + +/* ---------- + * get_sublink_expr - Parse back a sublink + * ---------- + */ +static void +get_sublink_expr(SubLink *sublink, deparse_context *context) +{ + StringInfo buf = context->buf; + Query *query = (Query *) (sublink->subselect); + char *opname = NULL; + bool need_paren; + + if (sublink->subLinkType == ARRAY_SUBLINK) + appendStringInfoString(buf, "ARRAY("); + else + appendStringInfoChar(buf, '('); + + /* + * Note that we print the name of only the first operator, when there are + * multiple combining operators. This is an approximation that could go + * wrong in various scenarios (operators in different schemas, renamed + * operators, etc) but there is not a whole lot we can do about it, since + * the syntax allows only one operator to be shown. + */ + if (sublink->testexpr) + { + if (IsA(sublink->testexpr, OpExpr)) + { + /* single combining operator */ + OpExpr *opexpr = (OpExpr *) sublink->testexpr; + + get_rule_expr(linitial(opexpr->args), context, true); + opname = generate_operator_name(opexpr->opno, + exprType(linitial(opexpr->args)), + exprType(lsecond(opexpr->args))); + } + else if (IsA(sublink->testexpr, BoolExpr)) + { + /* multiple combining operators, = or <> cases */ + char *sep; + ListCell *l; + + appendStringInfoChar(buf, '('); + sep = ""; + foreach(l, ((BoolExpr *) sublink->testexpr)->args) + { + OpExpr *opexpr = lfirst_node(OpExpr, l); + + appendStringInfoString(buf, sep); + get_rule_expr(linitial(opexpr->args), context, true); + if (!opname) + opname = generate_operator_name(opexpr->opno, + exprType(linitial(opexpr->args)), + exprType(lsecond(opexpr->args))); + sep = ", "; + } + appendStringInfoChar(buf, ')'); + } + else if (IsA(sublink->testexpr, RowCompareExpr)) + { + /* multiple combining operators, < <= > >= cases */ + RowCompareExpr *rcexpr = (RowCompareExpr *) sublink->testexpr; + + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) rcexpr->largs, context, true); + opname = generate_operator_name(linitial_oid(rcexpr->opnos), + exprType(linitial(rcexpr->largs)), + exprType(linitial(rcexpr->rargs))); + appendStringInfoChar(buf, ')'); + } + else + elog(ERROR, "unrecognized testexpr type: %d", + (int) nodeTag(sublink->testexpr)); + } + + need_paren = true; + + switch (sublink->subLinkType) + { + case EXISTS_SUBLINK: + appendStringInfoString(buf, "EXISTS "); + break; + + case ANY_SUBLINK: + if (strcmp(opname, "=") == 0) /* Represent = ANY as IN */ + appendStringInfoString(buf, " IN "); + else + appendStringInfo(buf, " %s ANY ", opname); + break; + + case ALL_SUBLINK: + appendStringInfo(buf, " %s ALL ", opname); + break; + + case ROWCOMPARE_SUBLINK: + appendStringInfo(buf, " %s ", opname); + break; + + case EXPR_SUBLINK: + case MULTIEXPR_SUBLINK: + case ARRAY_SUBLINK: + need_paren = false; + break; + + case CTE_SUBLINK: /* shouldn't occur in a SubLink */ + default: + elog(ERROR, "unrecognized sublink type: %d", + (int) sublink->subLinkType); + break; + } + + if (need_paren) + appendStringInfoChar(buf, '('); + + get_query_def(query, buf, context->namespaces, NULL, false, + context->prettyFlags, context->wrapColumn, + context->indentLevel); + + if (need_paren) + appendStringInfoString(buf, "))"); + else + appendStringInfoChar(buf, ')'); +} + + +/* ---------- + * get_tablefunc - Parse back a table function + * ---------- + */ +static void +get_tablefunc(TableFunc *tf, deparse_context *context, bool showimplicit) +{ + StringInfo buf = context->buf; + + /* XMLTABLE is the only existing implementation. */ + + appendStringInfoString(buf, "XMLTABLE("); + + if (tf->ns_uris != NIL) + { + ListCell *lc1, + *lc2; + bool first = true; + + appendStringInfoString(buf, "XMLNAMESPACES ("); + forboth(lc1, tf->ns_uris, lc2, tf->ns_names) + { + Node *expr = (Node *) lfirst(lc1); + Value *ns_node = (Value *) lfirst(lc2); + + if (!first) + appendStringInfoString(buf, ", "); + else + first = false; + + if (ns_node != NULL) + { + get_rule_expr(expr, context, showimplicit); + appendStringInfo(buf, " AS %s", strVal(ns_node)); + } + else + { + appendStringInfoString(buf, "DEFAULT "); + get_rule_expr(expr, context, showimplicit); + } + } + appendStringInfoString(buf, "), "); + } + + appendStringInfoChar(buf, '('); + get_rule_expr((Node *) tf->rowexpr, context, showimplicit); + appendStringInfoString(buf, ") PASSING ("); + get_rule_expr((Node *) tf->docexpr, context, showimplicit); + appendStringInfoChar(buf, ')'); + + if (tf->colexprs != NIL) + { + ListCell *l1; + ListCell *l2; + ListCell *l3; + ListCell *l4; + ListCell *l5; + int colnum = 0; + + appendStringInfoString(buf, " COLUMNS "); + forfive(l1, tf->colnames, l2, tf->coltypes, l3, tf->coltypmods, + l4, tf->colexprs, l5, tf->coldefexprs) + { + char *colname = strVal(lfirst(l1)); + Oid typid = lfirst_oid(l2); + int32 typmod = lfirst_int(l3); + Node *colexpr = (Node *) lfirst(l4); + Node *coldefexpr = (Node *) lfirst(l5); + bool ordinality = (tf->ordinalitycol == colnum); + bool notnull = bms_is_member(colnum, tf->notnulls); + + if (colnum > 0) + appendStringInfoString(buf, ", "); + colnum++; + + appendStringInfo(buf, "%s %s", quote_identifier(colname), + ordinality ? "FOR ORDINALITY" : + format_type_with_typemod(typid, typmod)); + if (ordinality) + continue; + + if (coldefexpr != NULL) + { + appendStringInfoString(buf, " DEFAULT ("); + get_rule_expr((Node *) coldefexpr, context, showimplicit); + appendStringInfoChar(buf, ')'); + } + if (colexpr != NULL) + { + appendStringInfoString(buf, " PATH ("); + get_rule_expr((Node *) colexpr, context, showimplicit); + appendStringInfoChar(buf, ')'); + } + if (notnull) + appendStringInfoString(buf, " NOT NULL"); + } + } + + appendStringInfoChar(buf, ')'); +} + +/* ---------- + * get_from_clause - Parse back a FROM clause + * + * "prefix" is the keyword that denotes the start of the list of FROM + * elements. It is FROM when used to parse back SELECT and UPDATE, but + * is USING when parsing back DELETE. + * ---------- + */ +static void +get_from_clause(Query *query, const char *prefix, deparse_context *context) +{ + StringInfo buf = context->buf; + bool first = true; + ListCell *l; + + /* + * We use the query's jointree as a guide to what to print. However, we + * must ignore auto-added RTEs that are marked not inFromCl. (These can + * only appear at the top level of the jointree, so it's sufficient to + * check here.) This check also ensures we ignore the rule pseudo-RTEs + * for NEW and OLD. + */ + foreach(l, query->jointree->fromlist) + { + Node *jtnode = (Node *) lfirst(l); + + if (IsA(jtnode, RangeTblRef)) + { + int varno = ((RangeTblRef *) jtnode)->rtindex; + RangeTblEntry *rte = rt_fetch(varno, query->rtable); + + if (!rte->inFromCl) + continue; + } + + if (first) + { + appendContextKeyword(context, prefix, + -PRETTYINDENT_STD, PRETTYINDENT_STD, 2); + first = false; + + get_from_clause_item(jtnode, query, context); + } + else + { + StringInfoData itembuf; + + appendStringInfoString(buf, ", "); + + /* + * Put the new FROM item's text into itembuf so we can decide + * after we've got it whether or not it needs to go on a new line. + */ + initStringInfo(&itembuf); + context->buf = &itembuf; + + get_from_clause_item(jtnode, query, context); + + /* Restore context's output buffer */ + context->buf = buf; + + /* Consider line-wrapping if enabled */ + if (PRETTY_INDENT(context) && context->wrapColumn >= 0) + { + /* Does the new item start with a new line? */ + if (itembuf.len > 0 && itembuf.data[0] == '\n') + { + /* If so, we shouldn't add anything */ + /* instead, remove any trailing spaces currently in buf */ + removeStringInfoSpaces(buf); + } + else + { + char *trailing_nl; + + /* Locate the start of the current line in the buffer */ + trailing_nl = strrchr(buf->data, '\n'); + if (trailing_nl == NULL) + trailing_nl = buf->data; + else + trailing_nl++; + + /* + * Add a newline, plus some indentation, if the new item + * would cause an overflow. + */ + if (strlen(trailing_nl) + itembuf.len > context->wrapColumn) + appendContextKeyword(context, "", -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_VAR); + } + } + + /* Add the new item */ + appendBinaryStringInfo(buf, itembuf.data, itembuf.len); + + /* clean up */ + pfree(itembuf.data); + } + } +} + +static void +get_from_clause_item(Node *jtnode, Query *query, deparse_context *context) +{ + StringInfo buf = context->buf; + deparse_namespace *dpns = (deparse_namespace *) linitial(context->namespaces); + + if (IsA(jtnode, RangeTblRef)) + { + int varno = ((RangeTblRef *) jtnode)->rtindex; + RangeTblEntry *rte = rt_fetch(varno, query->rtable); + char *refname = get_rtable_name(varno, context); + deparse_columns *colinfo = deparse_columns_fetch(varno, dpns); + RangeTblFunction *rtfunc1 = NULL; + bool printalias; + + if (rte->lateral) + appendStringInfoString(buf, "LATERAL "); + + /* Print the FROM item proper */ + switch (rte->rtekind) + { + case RTE_RELATION: + /* Normal relation RTE */ + appendStringInfo(buf, "%s%s", + only_marker(rte), + generate_relation_name(rte->relid, + context->namespaces)); + break; + case RTE_SUBQUERY: + /* Subquery RTE */ + appendStringInfoChar(buf, '('); + get_query_def(rte->subquery, buf, context->namespaces, NULL, + true, + context->prettyFlags, context->wrapColumn, + context->indentLevel); + appendStringInfoChar(buf, ')'); + break; + case RTE_FUNCTION: + /* Function RTE */ + rtfunc1 = (RangeTblFunction *) linitial(rte->functions); + + /* + * Omit ROWS FROM() syntax for just one function, unless it + * has both a coldeflist and WITH ORDINALITY. If it has both, + * we must use ROWS FROM() syntax to avoid ambiguity about + * whether the coldeflist includes the ordinality column. + */ + if (list_length(rte->functions) == 1 && + (rtfunc1->funccolnames == NIL || !rte->funcordinality)) + { + get_rule_expr_funccall(rtfunc1->funcexpr, context, true); + /* we'll print the coldeflist below, if it has one */ + } + else + { + bool all_unnest; + ListCell *lc; + + /* + * If all the function calls in the list are to unnest, + * and none need a coldeflist, then collapse the list back + * down to UNNEST(args). (If we had more than one + * built-in unnest function, this would get more + * difficult.) + * + * XXX This is pretty ugly, since it makes not-terribly- + * future-proof assumptions about what the parser would do + * with the output; but the alternative is to emit our + * nonstandard ROWS FROM() notation for what might have + * been a perfectly spec-compliant multi-argument + * UNNEST(). + */ + all_unnest = true; + foreach(lc, rte->functions) + { + RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc); + + if (!IsA(rtfunc->funcexpr, FuncExpr) || + ((FuncExpr *) rtfunc->funcexpr)->funcid != F_UNNEST_ANYARRAY || + rtfunc->funccolnames != NIL) + { + all_unnest = false; + break; + } + } + + if (all_unnest) + { + List *allargs = NIL; + + foreach(lc, rte->functions) + { + RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc); + List *args = ((FuncExpr *) rtfunc->funcexpr)->args; + + allargs = list_concat(allargs, args); + } + + appendStringInfoString(buf, "UNNEST("); + get_rule_expr((Node *) allargs, context, true); + appendStringInfoChar(buf, ')'); + } + else + { + int funcno = 0; + + appendStringInfoString(buf, "ROWS FROM("); + foreach(lc, rte->functions) + { + RangeTblFunction *rtfunc = (RangeTblFunction *) lfirst(lc); + + if (funcno > 0) + appendStringInfoString(buf, ", "); + get_rule_expr_funccall(rtfunc->funcexpr, context, true); + if (rtfunc->funccolnames != NIL) + { + /* Reconstruct the column definition list */ + appendStringInfoString(buf, " AS "); + get_from_clause_coldeflist(rtfunc, + NULL, + context); + } + funcno++; + } + appendStringInfoChar(buf, ')'); + } + /* prevent printing duplicate coldeflist below */ + rtfunc1 = NULL; + } + if (rte->funcordinality) + appendStringInfoString(buf, " WITH ORDINALITY"); + break; + case RTE_TABLEFUNC: + get_tablefunc(rte->tablefunc, context, true); + break; + case RTE_VALUES: + /* Values list RTE */ + appendStringInfoChar(buf, '('); + get_values_def(rte->values_lists, context); + appendStringInfoChar(buf, ')'); + break; + case RTE_CTE: + appendStringInfoString(buf, quote_identifier(rte->ctename)); + break; + default: + elog(ERROR, "unrecognized RTE kind: %d", (int) rte->rtekind); + break; + } + + /* Print the relation alias, if needed */ + printalias = false; + if (rte->alias != NULL) + { + /* Always print alias if user provided one */ + printalias = true; + } + else if (colinfo->printaliases) + { + /* Always print alias if we need to print column aliases */ + printalias = true; + } + else if (rte->rtekind == RTE_RELATION) + { + /* + * No need to print alias if it's same as relation name (this + * would normally be the case, but not if set_rtable_names had to + * resolve a conflict). + */ + if (strcmp(refname, get_relation_name(rte->relid)) != 0) + printalias = true; + } + else if (rte->rtekind == RTE_FUNCTION) + { + /* + * For a function RTE, always print alias. This covers possible + * renaming of the function and/or instability of the + * FigureColname rules for things that aren't simple functions. + * Note we'd need to force it anyway for the columndef list case. + */ + printalias = true; + } + else if (rte->rtekind == RTE_VALUES) + { + /* Alias is syntactically required for VALUES */ + printalias = true; + } + else if (rte->rtekind == RTE_CTE) + { + /* + * No need to print alias if it's same as CTE name (this would + * normally be the case, but not if set_rtable_names had to + * resolve a conflict). + */ + if (strcmp(refname, rte->ctename) != 0) + printalias = true; + } + if (printalias) + appendStringInfo(buf, " %s", quote_identifier(refname)); + + /* Print the column definitions or aliases, if needed */ + if (rtfunc1 && rtfunc1->funccolnames != NIL) + { + /* Reconstruct the columndef list, which is also the aliases */ + get_from_clause_coldeflist(rtfunc1, colinfo, context); + } + else + { + /* Else print column aliases as needed */ + get_column_alias_list(colinfo, context); + } + + /* Tablesample clause must go after any alias */ + if (rte->rtekind == RTE_RELATION && rte->tablesample) + get_tablesample_def(rte->tablesample, context); + } + else if (IsA(jtnode, JoinExpr)) + { + JoinExpr *j = (JoinExpr *) jtnode; + deparse_columns *colinfo = deparse_columns_fetch(j->rtindex, dpns); + bool need_paren_on_right; + + need_paren_on_right = PRETTY_PAREN(context) && + !IsA(j->rarg, RangeTblRef) && + !(IsA(j->rarg, JoinExpr) && ((JoinExpr *) j->rarg)->alias != NULL); + + if (!PRETTY_PAREN(context) || j->alias != NULL) + appendStringInfoChar(buf, '('); + + get_from_clause_item(j->larg, query, context); + + switch (j->jointype) + { + case JOIN_INNER: + if (j->quals) + appendContextKeyword(context, " JOIN ", + -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_JOIN); + else + appendContextKeyword(context, " CROSS JOIN ", + -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_JOIN); + break; + case JOIN_LEFT: + appendContextKeyword(context, " LEFT JOIN ", + -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_JOIN); + break; + case JOIN_FULL: + appendContextKeyword(context, " FULL JOIN ", + -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_JOIN); + break; + case JOIN_RIGHT: + appendContextKeyword(context, " RIGHT JOIN ", + -PRETTYINDENT_STD, + PRETTYINDENT_STD, + PRETTYINDENT_JOIN); + break; + default: + elog(ERROR, "unrecognized join type: %d", + (int) j->jointype); + } + + if (need_paren_on_right) + appendStringInfoChar(buf, '('); + get_from_clause_item(j->rarg, query, context); + if (need_paren_on_right) + appendStringInfoChar(buf, ')'); + + if (j->usingClause) + { + ListCell *lc; + bool first = true; + + appendStringInfoString(buf, " USING ("); + /* Use the assigned names, not what's in usingClause */ + foreach(lc, colinfo->usingNames) + { + char *colname = (char *) lfirst(lc); + + if (first) + first = false; + else + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, quote_identifier(colname)); + } + appendStringInfoChar(buf, ')'); + + if (j->join_using_alias) + appendStringInfo(buf, " AS %s", + quote_identifier(j->join_using_alias->aliasname)); + } + else if (j->quals) + { + appendStringInfoString(buf, " ON "); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, '('); + get_rule_expr(j->quals, context, false); + if (!PRETTY_PAREN(context)) + appendStringInfoChar(buf, ')'); + } + else if (j->jointype != JOIN_INNER) + { + /* If we didn't say CROSS JOIN above, we must provide an ON */ + appendStringInfoString(buf, " ON TRUE"); + } + + if (!PRETTY_PAREN(context) || j->alias != NULL) + appendStringInfoChar(buf, ')'); + + /* Yes, it's correct to put alias after the right paren ... */ + if (j->alias != NULL) + { + /* + * Note that it's correct to emit an alias clause if and only if + * there was one originally. Otherwise we'd be converting a named + * join to unnamed or vice versa, which creates semantic + * subtleties we don't want. However, we might print a different + * alias name than was there originally. + */ + appendStringInfo(buf, " %s", + quote_identifier(get_rtable_name(j->rtindex, + context))); + get_column_alias_list(colinfo, context); + } + } + else + elog(ERROR, "unrecognized node type: %d", + (int) nodeTag(jtnode)); +} + +/* + * get_column_alias_list - print column alias list for an RTE + * + * Caller must already have printed the relation's alias name. + */ +static void +get_column_alias_list(deparse_columns *colinfo, deparse_context *context) +{ + StringInfo buf = context->buf; + int i; + bool first = true; + + /* Don't print aliases if not needed */ + if (!colinfo->printaliases) + return; + + for (i = 0; i < colinfo->num_new_cols; i++) + { + char *colname = colinfo->new_colnames[i]; + + if (first) + { + appendStringInfoChar(buf, '('); + first = false; + } + else + appendStringInfoString(buf, ", "); + appendStringInfoString(buf, quote_identifier(colname)); + } + if (!first) + appendStringInfoChar(buf, ')'); +} + +/* + * get_from_clause_coldeflist - reproduce FROM clause coldeflist + * + * When printing a top-level coldeflist (which is syntactically also the + * relation's column alias list), use column names from colinfo. But when + * printing a coldeflist embedded inside ROWS FROM(), we prefer to use the + * original coldeflist's names, which are available in rtfunc->funccolnames. + * Pass NULL for colinfo to select the latter behavior. + * + * The coldeflist is appended immediately (no space) to buf. Caller is + * responsible for ensuring that an alias or AS is present before it. + */ +static void +get_from_clause_coldeflist(RangeTblFunction *rtfunc, + deparse_columns *colinfo, + deparse_context *context) +{ + StringInfo buf = context->buf; + ListCell *l1; + ListCell *l2; + ListCell *l3; + ListCell *l4; + int i; + + appendStringInfoChar(buf, '('); + + i = 0; + forfour(l1, rtfunc->funccoltypes, + l2, rtfunc->funccoltypmods, + l3, rtfunc->funccolcollations, + l4, rtfunc->funccolnames) + { + Oid atttypid = lfirst_oid(l1); + int32 atttypmod = lfirst_int(l2); + Oid attcollation = lfirst_oid(l3); + char *attname; + + if (colinfo) + attname = colinfo->colnames[i]; + else + attname = strVal(lfirst(l4)); + + Assert(attname); /* shouldn't be any dropped columns here */ + + if (i > 0) + appendStringInfoString(buf, ", "); + appendStringInfo(buf, "%s %s", + quote_identifier(attname), + format_type_with_typemod(atttypid, atttypmod)); + if (OidIsValid(attcollation) && + attcollation != get_typcollation(atttypid)) + appendStringInfo(buf, " COLLATE %s", + generate_collation_name(attcollation)); + + i++; + } + + appendStringInfoChar(buf, ')'); +} + +/* + * get_tablesample_def - print a TableSampleClause + */ +static void +get_tablesample_def(TableSampleClause *tablesample, deparse_context *context) +{ + StringInfo buf = context->buf; + Oid argtypes[1]; + int nargs; + ListCell *l; + + /* + * We should qualify the handler's function name if it wouldn't be + * resolved by lookup in the current search path. + */ + argtypes[0] = INTERNALOID; + appendStringInfo(buf, " TABLESAMPLE %s (", + generate_function_name(tablesample->tsmhandler, 1, + NIL, argtypes, + false, NULL, EXPR_KIND_NONE)); + + nargs = 0; + foreach(l, tablesample->args) + { + if (nargs++ > 0) + appendStringInfoString(buf, ", "); + get_rule_expr((Node *) lfirst(l), context, false); + } + appendStringInfoChar(buf, ')'); + + if (tablesample->repeatable != NULL) + { + appendStringInfoString(buf, " REPEATABLE ("); + get_rule_expr((Node *) tablesample->repeatable, context, false); + appendStringInfoChar(buf, ')'); + } +} + +/* + * get_opclass_name - fetch name of an index operator class + * + * The opclass name is appended (after a space) to buf. + * + * Output is suppressed if the opclass is the default for the given + * actual_datatype. (If you don't want this behavior, just pass + * InvalidOid for actual_datatype.) + */ +static void +get_opclass_name(Oid opclass, Oid actual_datatype, + StringInfo buf) +{ + HeapTuple ht_opc; + Form_pg_opclass opcrec; + char *opcname; + char *nspname; + + ht_opc = SearchSysCache1(CLAOID, ObjectIdGetDatum(opclass)); + if (!HeapTupleIsValid(ht_opc)) + elog(ERROR, "cache lookup failed for opclass %u", opclass); + opcrec = (Form_pg_opclass) GETSTRUCT(ht_opc); + + if (!OidIsValid(actual_datatype) || + GetDefaultOpClass(actual_datatype, opcrec->opcmethod) != opclass) + { + /* Okay, we need the opclass name. Do we need to qualify it? */ + opcname = NameStr(opcrec->opcname); + if (OpclassIsVisible(opclass)) + appendStringInfo(buf, " %s", quote_identifier(opcname)); + else + { + nspname = get_namespace_name(opcrec->opcnamespace); + appendStringInfo(buf, " %s.%s", + quote_identifier(nspname), + quote_identifier(opcname)); + } + } + ReleaseSysCache(ht_opc); +} + +/* + * generate_opclass_name + * Compute the name to display for a opclass specified by OID + * + * The result includes all necessary quoting and schema-prefixing. + */ +char * +generate_opclass_name(Oid opclass) +{ + StringInfoData buf; + + initStringInfo(&buf); + get_opclass_name(opclass, InvalidOid, &buf); + + return &buf.data[1]; /* get_opclass_name() prepends space */ +} + +/* + * processIndirection - take care of array and subfield assignment + * + * We strip any top-level FieldStore or assignment SubscriptingRef nodes that + * appear in the input, printing them as decoration for the base column + * name (which we assume the caller just printed). We might also need to + * strip CoerceToDomain nodes, but only ones that appear above assignment + * nodes. + * + * Returns the subexpression that's to be assigned. + */ +static Node * +processIndirection(Node *node, deparse_context *context) +{ + StringInfo buf = context->buf; + CoerceToDomain *cdomain = NULL; + + for (;;) + { + if (node == NULL) + break; + if (IsA(node, FieldStore)) + { + FieldStore *fstore = (FieldStore *) node; + Oid typrelid; + char *fieldname; + + /* lookup tuple type */ + typrelid = get_typ_typrelid(fstore->resulttype); + if (!OidIsValid(typrelid)) + elog(ERROR, "argument type %s of FieldStore is not a tuple type", + format_type_be(fstore->resulttype)); + + /* + * Print the field name. There should only be one target field in + * stored rules. There could be more than that in executable + * target lists, but this function cannot be used for that case. + */ + Assert(list_length(fstore->fieldnums) == 1); + fieldname = get_attname(typrelid, + linitial_int(fstore->fieldnums), false); + appendStringInfo(buf, ".%s", quote_identifier(fieldname)); + + /* + * We ignore arg since it should be an uninteresting reference to + * the target column or subcolumn. + */ + node = (Node *) linitial(fstore->newvals); + } + else if (IsA(node, SubscriptingRef)) + { + SubscriptingRef *sbsref = (SubscriptingRef *) node; + + if (sbsref->refassgnexpr == NULL) + break; + + printSubscripts(sbsref, context); + + /* + * We ignore refexpr since it should be an uninteresting reference + * to the target column or subcolumn. + */ + node = (Node *) sbsref->refassgnexpr; + } + else if (IsA(node, CoerceToDomain)) + { + cdomain = (CoerceToDomain *) node; + /* If it's an explicit domain coercion, we're done */ + if (cdomain->coercionformat != COERCE_IMPLICIT_CAST) + break; + /* Tentatively descend past the CoerceToDomain */ + node = (Node *) cdomain->arg; + } + else + break; + } + + /* + * If we descended past a CoerceToDomain whose argument turned out not to + * be a FieldStore or array assignment, back up to the CoerceToDomain. + * (This is not enough to be fully correct if there are nested implicit + * CoerceToDomains, but such cases shouldn't ever occur.) + */ + if (cdomain && node == (Node *) cdomain->arg) + node = (Node *) cdomain; + + return node; +} + +static void +printSubscripts(SubscriptingRef *sbsref, deparse_context *context) +{ + StringInfo buf = context->buf; + ListCell *lowlist_item; + ListCell *uplist_item; + + lowlist_item = list_head(sbsref->reflowerindexpr); /* could be NULL */ + foreach(uplist_item, sbsref->refupperindexpr) + { + appendStringInfoChar(buf, '['); + if (lowlist_item) + { + /* If subexpression is NULL, get_rule_expr prints nothing */ + get_rule_expr((Node *) lfirst(lowlist_item), context, false); + appendStringInfoChar(buf, ':'); + lowlist_item = lnext(sbsref->reflowerindexpr, lowlist_item); + } + /* If subexpression is NULL, get_rule_expr prints nothing */ + get_rule_expr((Node *) lfirst(uplist_item), context, false); + appendStringInfoChar(buf, ']'); + } +} + +/* + * quote_identifier - Quote an identifier only if needed + * + * When quotes are needed, we palloc the required space; slightly + * space-wasteful but well worth it for notational simplicity. + */ +const char * +quote_identifier(const char *ident) +{ + /* + * Can avoid quoting if ident starts with a lowercase letter or underscore + * and contains only lowercase letters, digits, and underscores, *and* is + * not any SQL keyword. Otherwise, supply quotes. + */ + int nquotes = 0; + bool safe; + const char *ptr; + char *result; + char *optr; + + /* + * would like to use <ctype.h> macros here, but they might yield unwanted + * locale-specific results... + */ + safe = ((ident[0] >= 'a' && ident[0] <= 'z') || ident[0] == '_'); + + for (ptr = ident; *ptr; ptr++) + { + char ch = *ptr; + + if ((ch >= 'a' && ch <= 'z') || + (ch >= '0' && ch <= '9') || + (ch == '_')) + { + /* okay */ + } + else + { + safe = false; + if (ch == '"') + nquotes++; + } + } + + if (quote_all_identifiers) + safe = false; + + if (safe) + { + /* + * Check for keyword. We quote keywords except for unreserved ones. + * (In some cases we could avoid quoting a col_name or type_func_name + * keyword, but it seems much harder than it's worth to tell that.) + * + * Note: ScanKeywordLookup() does case-insensitive comparison, but + * that's fine, since we already know we have all-lower-case. + */ + int kwnum = ScanKeywordLookup(ident, &ScanKeywords); + + if (kwnum >= 0 && ScanKeywordCategories[kwnum] != UNRESERVED_KEYWORD) + safe = false; + } + + if (safe) + return ident; /* no change needed */ + + result = (char *) palloc(strlen(ident) + nquotes + 2 + 1); + + optr = result; + *optr++ = '"'; + for (ptr = ident; *ptr; ptr++) + { + char ch = *ptr; + + if (ch == '"') + *optr++ = '"'; + *optr++ = ch; + } + *optr++ = '"'; + *optr = '\0'; + + return result; +} + +/* + * quote_qualified_identifier - Quote a possibly-qualified identifier + * + * Return a name of the form qualifier.ident, or just ident if qualifier + * is NULL, quoting each component if necessary. The result is palloc'd. + */ +char * +quote_qualified_identifier(const char *qualifier, + const char *ident) +{ + StringInfoData buf; + + initStringInfo(&buf); + if (qualifier) + appendStringInfo(&buf, "%s.", quote_identifier(qualifier)); + appendStringInfoString(&buf, quote_identifier(ident)); + return buf.data; +} + +/* + * get_relation_name + * Get the unqualified name of a relation specified by OID + * + * This differs from the underlying get_rel_name() function in that it will + * throw error instead of silently returning NULL if the OID is bad. + */ +static char * +get_relation_name(Oid relid) +{ + char *relname = get_rel_name(relid); + + if (!relname) + elog(ERROR, "cache lookup failed for relation %u", relid); + return relname; +} + +/* + * generate_relation_name + * Compute the name to display for a relation specified by OID + * + * The result includes all necessary quoting and schema-prefixing. + * + * If namespaces isn't NIL, it must be a list of deparse_namespace nodes. + * We will forcibly qualify the relation name if it equals any CTE name + * visible in the namespace list. + */ +static char * +generate_relation_name(Oid relid, List *namespaces) +{ + HeapTuple tp; + Form_pg_class reltup; + bool need_qual; + ListCell *nslist; + char *relname; + char *nspname; + char *result; + + tp = SearchSysCache1(RELOID, ObjectIdGetDatum(relid)); + if (!HeapTupleIsValid(tp)) + elog(ERROR, "cache lookup failed for relation %u", relid); + reltup = (Form_pg_class) GETSTRUCT(tp); + relname = NameStr(reltup->relname); + + /* Check for conflicting CTE name */ + need_qual = false; + foreach(nslist, namespaces) + { + deparse_namespace *dpns = (deparse_namespace *) lfirst(nslist); + ListCell *ctlist; + + foreach(ctlist, dpns->ctes) + { + CommonTableExpr *cte = (CommonTableExpr *) lfirst(ctlist); + + if (strcmp(cte->ctename, relname) == 0) + { + need_qual = true; + break; + } + } + if (need_qual) + break; + } + + /* Otherwise, qualify the name if not visible in search path */ + if (!need_qual) + need_qual = !RelationIsVisible(relid); + + if (need_qual) + nspname = get_namespace_name(reltup->relnamespace); + else + nspname = NULL; + + result = quote_qualified_identifier(nspname, relname); + + ReleaseSysCache(tp); + + return result; +} + +/* + * generate_qualified_relation_name + * Compute the name to display for a relation specified by OID + * + * As above, but unconditionally schema-qualify the name. + */ +static char * +generate_qualified_relation_name(Oid relid) +{ + HeapTuple tp; + Form_pg_class reltup; + char *relname; + char *nspname; + char *result; + + tp = SearchSysCache1(RELOID, ObjectIdGetDatum(relid)); + if (!HeapTupleIsValid(tp)) + elog(ERROR, "cache lookup failed for relation %u", relid); + reltup = (Form_pg_class) GETSTRUCT(tp); + relname = NameStr(reltup->relname); + + nspname = get_namespace_name(reltup->relnamespace); + if (!nspname) + elog(ERROR, "cache lookup failed for namespace %u", + reltup->relnamespace); + + result = quote_qualified_identifier(nspname, relname); + + ReleaseSysCache(tp); + + return result; +} + +/* + * generate_function_name + * Compute the name to display for a function specified by OID, + * given that it is being called with the specified actual arg names and + * types. (Those matter because of ambiguous-function resolution rules.) + * + * If we're dealing with a potentially variadic function (in practice, this + * means a FuncExpr or Aggref, not some other way of calling a function), then + * has_variadic must specify whether variadic arguments have been merged, + * and *use_variadic_p will be set to indicate whether to print VARIADIC in + * the output. For non-FuncExpr cases, has_variadic should be false and + * use_variadic_p can be NULL. + * + * The result includes all necessary quoting and schema-prefixing. + */ +static char * +generate_function_name(Oid funcid, int nargs, List *argnames, Oid *argtypes, + bool has_variadic, bool *use_variadic_p, + ParseExprKind special_exprkind) +{ + char *result; + HeapTuple proctup; + Form_pg_proc procform; + char *proname; + bool use_variadic; + char *nspname; + FuncDetailCode p_result; + Oid p_funcid; + Oid p_rettype; + bool p_retset; + int p_nvargs; + Oid p_vatype; + Oid *p_true_typeids; + bool force_qualify = false; + + proctup = SearchSysCache1(PROCOID, ObjectIdGetDatum(funcid)); + if (!HeapTupleIsValid(proctup)) + elog(ERROR, "cache lookup failed for function %u", funcid); + procform = (Form_pg_proc) GETSTRUCT(proctup); + proname = NameStr(procform->proname); + + /* + * Due to parser hacks to avoid needing to reserve CUBE, we need to force + * qualification in some special cases. + */ + if (special_exprkind == EXPR_KIND_GROUP_BY) + { + if (strcmp(proname, "cube") == 0 || strcmp(proname, "rollup") == 0) + force_qualify = true; + } + + /* + * Determine whether VARIADIC should be printed. We must do this first + * since it affects the lookup rules in func_get_detail(). + * + * We always print VARIADIC if the function has a merged variadic-array + * argument. Note that this is always the case for functions taking a + * VARIADIC argument type other than VARIADIC ANY. If we omitted VARIADIC + * and printed the array elements as separate arguments, the call could + * match a newer non-VARIADIC function. + */ + if (use_variadic_p) + { + /* Parser should not have set funcvariadic unless fn is variadic */ + Assert(!has_variadic || OidIsValid(procform->provariadic)); + use_variadic = has_variadic; + *use_variadic_p = use_variadic; + } + else + { + Assert(!has_variadic); + use_variadic = false; + } + + /* + * The idea here is to schema-qualify only if the parser would fail to + * resolve the correct function given the unqualified func name with the + * specified argtypes and VARIADIC flag. But if we already decided to + * force qualification, then we can skip the lookup and pretend we didn't + * find it. + */ + if (!force_qualify) + p_result = func_get_detail(list_make1(makeString(proname)), + NIL, argnames, nargs, argtypes, + !use_variadic, true, false, + &p_funcid, &p_rettype, + &p_retset, &p_nvargs, &p_vatype, + &p_true_typeids, NULL); + else + { + p_result = FUNCDETAIL_NOTFOUND; + p_funcid = InvalidOid; + } + + if ((p_result == FUNCDETAIL_NORMAL || + p_result == FUNCDETAIL_AGGREGATE || + p_result == FUNCDETAIL_WINDOWFUNC) && + p_funcid == funcid) + nspname = NULL; + else + nspname = get_namespace_name(procform->pronamespace); + + result = quote_qualified_identifier(nspname, proname); + + ReleaseSysCache(proctup); + + return result; +} + +/* + * generate_operator_name + * Compute the name to display for an operator specified by OID, + * given that it is being called with the specified actual arg types. + * (Arg types matter because of ambiguous-operator resolution rules. + * Pass InvalidOid for unused arg of a unary operator.) + * + * The result includes all necessary quoting and schema-prefixing, + * plus the OPERATOR() decoration needed to use a qualified operator name + * in an expression. + */ +static char * +generate_operator_name(Oid operid, Oid arg1, Oid arg2) +{ + StringInfoData buf; + HeapTuple opertup; + Form_pg_operator operform; + char *oprname; + char *nspname; + Operator p_result; + + initStringInfo(&buf); + + opertup = SearchSysCache1(OPEROID, ObjectIdGetDatum(operid)); + if (!HeapTupleIsValid(opertup)) + elog(ERROR, "cache lookup failed for operator %u", operid); + operform = (Form_pg_operator) GETSTRUCT(opertup); + oprname = NameStr(operform->oprname); + + /* + * The idea here is to schema-qualify only if the parser would fail to + * resolve the correct operator given the unqualified op name with the + * specified argtypes. + */ + switch (operform->oprkind) + { + case 'b': + p_result = oper(NULL, list_make1(makeString(oprname)), arg1, arg2, + true, -1); + break; + case 'l': + p_result = left_oper(NULL, list_make1(makeString(oprname)), arg2, + true, -1); + break; + default: + elog(ERROR, "unrecognized oprkind: %d", operform->oprkind); + p_result = NULL; /* keep compiler quiet */ + break; + } + + if (p_result != NULL && oprid(p_result) == operid) + nspname = NULL; + else + { + nspname = get_namespace_name(operform->oprnamespace); + appendStringInfo(&buf, "OPERATOR(%s.", quote_identifier(nspname)); + } + + appendStringInfoString(&buf, oprname); + + if (nspname) + appendStringInfoChar(&buf, ')'); + + if (p_result != NULL) + ReleaseSysCache(p_result); + + ReleaseSysCache(opertup); + + return buf.data; +} + +/* + * generate_operator_clause --- generate a binary-operator WHERE clause + * + * This is used for internally-generated-and-executed SQL queries, where + * precision is essential and readability is secondary. The basic + * requirement is to append "leftop op rightop" to buf, where leftop and + * rightop are given as strings and are assumed to yield types leftoptype + * and rightoptype; the operator is identified by OID. The complexity + * comes from needing to be sure that the parser will select the desired + * operator when the query is parsed. We always name the operator using + * OPERATOR(schema.op) syntax, so as to avoid search-path uncertainties. + * We have to emit casts too, if either input isn't already the input type + * of the operator; else we are at the mercy of the parser's heuristics for + * ambiguous-operator resolution. The caller must ensure that leftop and + * rightop are suitable arguments for a cast operation; it's best to insert + * parentheses if they aren't just variables or parameters. + */ +void +generate_operator_clause(StringInfo buf, + const char *leftop, Oid leftoptype, + Oid opoid, + const char *rightop, Oid rightoptype) +{ + HeapTuple opertup; + Form_pg_operator operform; + char *oprname; + char *nspname; + + opertup = SearchSysCache1(OPEROID, ObjectIdGetDatum(opoid)); + if (!HeapTupleIsValid(opertup)) + elog(ERROR, "cache lookup failed for operator %u", opoid); + operform = (Form_pg_operator) GETSTRUCT(opertup); + Assert(operform->oprkind == 'b'); + oprname = NameStr(operform->oprname); + + nspname = get_namespace_name(operform->oprnamespace); + + appendStringInfoString(buf, leftop); + if (leftoptype != operform->oprleft) + add_cast_to(buf, operform->oprleft); + appendStringInfo(buf, " OPERATOR(%s.", quote_identifier(nspname)); + appendStringInfoString(buf, oprname); + appendStringInfo(buf, ") %s", rightop); + if (rightoptype != operform->oprright) + add_cast_to(buf, operform->oprright); + + ReleaseSysCache(opertup); +} + +/* + * Add a cast specification to buf. We spell out the type name the hard way, + * intentionally not using format_type_be(). This is to avoid corner cases + * for CHARACTER, BIT, and perhaps other types, where specifying the type + * using SQL-standard syntax results in undesirable data truncation. By + * doing it this way we can be certain that the cast will have default (-1) + * target typmod. + */ +static void +add_cast_to(StringInfo buf, Oid typid) +{ + HeapTuple typetup; + Form_pg_type typform; + char *typname; + char *nspname; + + typetup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid)); + if (!HeapTupleIsValid(typetup)) + elog(ERROR, "cache lookup failed for type %u", typid); + typform = (Form_pg_type) GETSTRUCT(typetup); + + typname = NameStr(typform->typname); + nspname = get_namespace_name(typform->typnamespace); + + appendStringInfo(buf, "::%s.%s", + quote_identifier(nspname), quote_identifier(typname)); + + ReleaseSysCache(typetup); +} + +/* + * generate_qualified_type_name + * Compute the name to display for a type specified by OID + * + * This is different from format_type_be() in that we unconditionally + * schema-qualify the name. That also means no special syntax for + * SQL-standard type names ... although in current usage, this should + * only get used for domains, so such cases wouldn't occur anyway. + */ +static char * +generate_qualified_type_name(Oid typid) +{ + HeapTuple tp; + Form_pg_type typtup; + char *typname; + char *nspname; + char *result; + + tp = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid)); + if (!HeapTupleIsValid(tp)) + elog(ERROR, "cache lookup failed for type %u", typid); + typtup = (Form_pg_type) GETSTRUCT(tp); + typname = NameStr(typtup->typname); + + nspname = get_namespace_name(typtup->typnamespace); + if (!nspname) + elog(ERROR, "cache lookup failed for namespace %u", + typtup->typnamespace); + + result = quote_qualified_identifier(nspname, typname); + + ReleaseSysCache(tp); + + return result; +} + +/* + * generate_collation_name + * Compute the name to display for a collation specified by OID + * + * The result includes all necessary quoting and schema-prefixing. + */ +char * +generate_collation_name(Oid collid) +{ + HeapTuple tp; + Form_pg_collation colltup; + char *collname; + char *nspname; + char *result; + + tp = SearchSysCache1(COLLOID, ObjectIdGetDatum(collid)); + if (!HeapTupleIsValid(tp)) + elog(ERROR, "cache lookup failed for collation %u", collid); + colltup = (Form_pg_collation) GETSTRUCT(tp); + collname = NameStr(colltup->collname); + + if (!CollationIsVisible(collid)) + nspname = get_namespace_name(colltup->collnamespace); + else + nspname = NULL; + + result = quote_qualified_identifier(nspname, collname); + + ReleaseSysCache(tp); + + return result; +} + +/* + * Given a C string, produce a TEXT datum. + * + * We assume that the input was palloc'd and may be freed. + */ +static text * +string_to_text(char *str) +{ + text *result; + + result = cstring_to_text(str); + pfree(str); + return result; +} + +/* + * Generate a C string representing a relation options from text[] datum. + */ +static void +get_reloptions(StringInfo buf, Datum reloptions) +{ + Datum *options; + int noptions; + int i; + + deconstruct_array(DatumGetArrayTypeP(reloptions), + TEXTOID, -1, false, TYPALIGN_INT, + &options, NULL, &noptions); + + for (i = 0; i < noptions; i++) + { + char *option = TextDatumGetCString(options[i]); + char *name; + char *separator; + char *value; + + /* + * Each array element should have the form name=value. If the "=" is + * missing for some reason, treat it like an empty value. + */ + name = option; + separator = strchr(option, '='); + if (separator) + { + *separator = '\0'; + value = separator + 1; + } + else + value = ""; + + if (i > 0) + appendStringInfoString(buf, ", "); + appendStringInfo(buf, "%s=", quote_identifier(name)); + + /* + * In general we need to quote the value; but to avoid unnecessary + * clutter, do not quote if it is an identifier that would not need + * quoting. (We could also allow numbers, but that is a bit trickier + * than it looks --- for example, are leading zeroes significant? We + * don't want to assume very much here about what custom reloptions + * might mean.) + */ + if (quote_identifier(value) == value) + appendStringInfoString(buf, value); + else + simple_quote_literal(buf, value); + + pfree(option); + } +} + +/* + * Generate a C string representing a relation's reloptions, or NULL if none. + */ +static char * +flatten_reloptions(Oid relid) +{ + char *result = NULL; + HeapTuple tuple; + Datum reloptions; + bool isnull; + + tuple = SearchSysCache1(RELOID, ObjectIdGetDatum(relid)); + if (!HeapTupleIsValid(tuple)) + elog(ERROR, "cache lookup failed for relation %u", relid); + + reloptions = SysCacheGetAttr(RELOID, tuple, + Anum_pg_class_reloptions, &isnull); + if (!isnull) + { + StringInfoData buf; + + initStringInfo(&buf); + get_reloptions(&buf, reloptions); + + result = buf.data; + } + + ReleaseSysCache(tuple); + + return result; +} + +/* + * get_range_partbound_string + * A C string representation of one range partition bound + */ +char * +get_range_partbound_string(List *bound_datums) +{ + deparse_context context; + StringInfo buf = makeStringInfo(); + ListCell *cell; + char *sep; + + memset(&context, 0, sizeof(deparse_context)); + context.buf = buf; + + appendStringInfoChar(buf, '('); + sep = ""; + foreach(cell, bound_datums) + { + PartitionRangeDatum *datum = + castNode(PartitionRangeDatum, lfirst(cell)); + + appendStringInfoString(buf, sep); + if (datum->kind == PARTITION_RANGE_DATUM_MINVALUE) + appendStringInfoString(buf, "MINVALUE"); + else if (datum->kind == PARTITION_RANGE_DATUM_MAXVALUE) + appendStringInfoString(buf, "MAXVALUE"); + else + { + Const *val = castNode(Const, datum->value); + + get_const_expr(val, &context, -1); + } + sep = ", "; + } + appendStringInfoChar(buf, ')'); + + return buf->data; +} |