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Diffstat (limited to 'contrib/postgres_fdw/postgres_fdw.h')
| -rw-r--r-- | contrib/postgres_fdw/postgres_fdw.h | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/contrib/postgres_fdw/postgres_fdw.h b/contrib/postgres_fdw/postgres_fdw.h new file mode 100644 index 0000000..bd4e592 --- /dev/null +++ b/contrib/postgres_fdw/postgres_fdw.h @@ -0,0 +1,238 @@ +/*------------------------------------------------------------------------- + * + * postgres_fdw.h + * Foreign-data wrapper for remote PostgreSQL servers + * + * Portions Copyright (c) 2012-2021, PostgreSQL Global Development Group + * + * IDENTIFICATION + * contrib/postgres_fdw/postgres_fdw.h + * + *------------------------------------------------------------------------- + */ +#ifndef POSTGRES_FDW_H +#define POSTGRES_FDW_H + +#include "foreign/foreign.h" +#include "lib/stringinfo.h" +#include "libpq-fe.h" +#include "nodes/execnodes.h" +#include "nodes/pathnodes.h" +#include "utils/relcache.h" + +/* + * FDW-specific planner information kept in RelOptInfo.fdw_private for a + * postgres_fdw foreign table. For a baserel, this struct is created by + * postgresGetForeignRelSize, although some fields are not filled till later. + * postgresGetForeignJoinPaths creates it for a joinrel, and + * postgresGetForeignUpperPaths creates it for an upperrel. + */ +typedef struct PgFdwRelationInfo +{ + /* + * True means that the relation can be pushed down. Always true for simple + * foreign scan. + */ + bool pushdown_safe; + + /* + * Restriction clauses, divided into safe and unsafe to pushdown subsets. + * All entries in these lists should have RestrictInfo wrappers; that + * improves efficiency of selectivity and cost estimation. + */ + List *remote_conds; + List *local_conds; + + /* Actual remote restriction clauses for scan (sans RestrictInfos) */ + List *final_remote_exprs; + + /* Bitmap of attr numbers we need to fetch from the remote server. */ + Bitmapset *attrs_used; + + /* True means that the query_pathkeys is safe to push down */ + bool qp_is_pushdown_safe; + + /* Cost and selectivity of local_conds. */ + QualCost local_conds_cost; + Selectivity local_conds_sel; + + /* Selectivity of join conditions */ + Selectivity joinclause_sel; + + /* Estimated size and cost for a scan, join, or grouping/aggregation. */ + double rows; + int width; + Cost startup_cost; + Cost total_cost; + + /* + * Estimated number of rows fetched from the foreign server, and costs + * excluding costs for transferring those rows from the foreign server. + * These are only used by estimate_path_cost_size(). + */ + double retrieved_rows; + Cost rel_startup_cost; + Cost rel_total_cost; + + /* Options extracted from catalogs. */ + bool use_remote_estimate; + Cost fdw_startup_cost; + Cost fdw_tuple_cost; + List *shippable_extensions; /* OIDs of shippable extensions */ + bool async_capable; + + /* Cached catalog information. */ + ForeignTable *table; + ForeignServer *server; + UserMapping *user; /* only set in use_remote_estimate mode */ + + int fetch_size; /* fetch size for this remote table */ + + /* + * Name of the relation, for use while EXPLAINing ForeignScan. It is used + * for join and upper relations but is set for all relations. For a base + * relation, this is really just the RT index as a string; we convert that + * while producing EXPLAIN output. For join and upper relations, the name + * indicates which base foreign tables are included and the join type or + * aggregation type used. + */ + char *relation_name; + + /* Join information */ + RelOptInfo *outerrel; + RelOptInfo *innerrel; + JoinType jointype; + /* joinclauses contains only JOIN/ON conditions for an outer join */ + List *joinclauses; /* List of RestrictInfo */ + + /* Upper relation information */ + UpperRelationKind stage; + + /* Grouping information */ + List *grouped_tlist; + + /* Subquery information */ + bool make_outerrel_subquery; /* do we deparse outerrel as a + * subquery? */ + bool make_innerrel_subquery; /* do we deparse innerrel as a + * subquery? */ + Relids lower_subquery_rels; /* all relids appearing in lower + * subqueries */ + + /* + * Index of the relation. It is used to create an alias to a subquery + * representing the relation. + */ + int relation_index; +} PgFdwRelationInfo; + +/* + * Extra control information relating to a connection. + */ +typedef struct PgFdwConnState +{ + AsyncRequest *pendingAreq; /* pending async request */ +} PgFdwConnState; + +/* in postgres_fdw.c */ +extern int set_transmission_modes(void); +extern void reset_transmission_modes(int nestlevel); +extern void process_pending_request(AsyncRequest *areq); + +/* in connection.c */ +extern PGconn *GetConnection(UserMapping *user, bool will_prep_stmt, + PgFdwConnState **state); +extern void ReleaseConnection(PGconn *conn); +extern unsigned int GetCursorNumber(PGconn *conn); +extern unsigned int GetPrepStmtNumber(PGconn *conn); +extern void do_sql_command(PGconn *conn, const char *sql); +extern PGresult *pgfdw_get_result(PGconn *conn, const char *query); +extern PGresult *pgfdw_exec_query(PGconn *conn, const char *query, + PgFdwConnState *state); +extern void pgfdw_report_error(int elevel, PGresult *res, PGconn *conn, + bool clear, const char *sql); + +/* in option.c */ +extern int ExtractConnectionOptions(List *defelems, + const char **keywords, + const char **values); +extern List *ExtractExtensionList(const char *extensionsString, + bool warnOnMissing); + +/* in deparse.c */ +extern void classifyConditions(PlannerInfo *root, + RelOptInfo *baserel, + List *input_conds, + List **remote_conds, + List **local_conds); +extern bool is_foreign_expr(PlannerInfo *root, + RelOptInfo *baserel, + Expr *expr); +extern bool is_foreign_param(PlannerInfo *root, + RelOptInfo *baserel, + Expr *expr); +extern bool is_foreign_pathkey(PlannerInfo *root, + RelOptInfo *baserel, + PathKey *pathkey); +extern void deparseInsertSql(StringInfo buf, RangeTblEntry *rte, + Index rtindex, Relation rel, + List *targetAttrs, bool doNothing, + List *withCheckOptionList, List *returningList, + List **retrieved_attrs, int *values_end_len); +extern void rebuildInsertSql(StringInfo buf, Relation rel, + char *orig_query, List *target_attrs, + int values_end_len, int num_params, + int num_rows); +extern void deparseUpdateSql(StringInfo buf, RangeTblEntry *rte, + Index rtindex, Relation rel, + List *targetAttrs, + List *withCheckOptionList, List *returningList, + List **retrieved_attrs); +extern void deparseDirectUpdateSql(StringInfo buf, PlannerInfo *root, + Index rtindex, Relation rel, + RelOptInfo *foreignrel, + List *targetlist, + List *targetAttrs, + List *remote_conds, + List **params_list, + List *returningList, + List **retrieved_attrs); +extern void deparseDeleteSql(StringInfo buf, RangeTblEntry *rte, + Index rtindex, Relation rel, + List *returningList, + List **retrieved_attrs); +extern void deparseDirectDeleteSql(StringInfo buf, PlannerInfo *root, + Index rtindex, Relation rel, + RelOptInfo *foreignrel, + List *remote_conds, + List **params_list, + List *returningList, + List **retrieved_attrs); +extern void deparseAnalyzeSizeSql(StringInfo buf, Relation rel); +extern void deparseAnalyzeSql(StringInfo buf, Relation rel, + List **retrieved_attrs); +extern void deparseTruncateSql(StringInfo buf, + List *rels, + DropBehavior behavior, + bool restart_seqs); +extern void deparseStringLiteral(StringInfo buf, const char *val); +extern EquivalenceMember *find_em_for_rel(PlannerInfo *root, + EquivalenceClass *ec, + RelOptInfo *rel); +extern EquivalenceMember *find_em_for_rel_target(PlannerInfo *root, + EquivalenceClass *ec, + RelOptInfo *rel); +extern List *build_tlist_to_deparse(RelOptInfo *foreignrel); +extern void deparseSelectStmtForRel(StringInfo buf, PlannerInfo *root, + RelOptInfo *foreignrel, List *tlist, + List *remote_conds, List *pathkeys, + bool has_final_sort, bool has_limit, + bool is_subquery, + List **retrieved_attrs, List **params_list); +extern const char *get_jointype_name(JoinType jointype); + +/* in shippable.c */ +extern bool is_builtin(Oid objectId); +extern bool is_shippable(Oid objectId, Oid classId, PgFdwRelationInfo *fpinfo); + +#endif /* POSTGRES_FDW_H */ |