diff options
Diffstat (limited to 'src/backend/commands/dropcmds.c')
| -rw-r--r-- | src/backend/commands/dropcmds.c | 493 |
1 files changed, 493 insertions, 0 deletions
diff --git a/src/backend/commands/dropcmds.c b/src/backend/commands/dropcmds.c new file mode 100644 index 0000000..97e5e9a --- /dev/null +++ b/src/backend/commands/dropcmds.c @@ -0,0 +1,493 @@ +/*------------------------------------------------------------------------- + * + * dropcmds.c + * handle various "DROP" operations + * + * Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group + * Portions Copyright (c) 1994, Regents of the University of California + * + * + * IDENTIFICATION + * src/backend/commands/dropcmds.c + * + *------------------------------------------------------------------------- + */ +#include "postgres.h" + +#include "access/htup_details.h" +#include "access/table.h" +#include "access/xact.h" +#include "catalog/dependency.h" +#include "catalog/namespace.h" +#include "catalog/objectaddress.h" +#include "catalog/pg_class.h" +#include "catalog/pg_proc.h" +#include "commands/defrem.h" +#include "miscadmin.h" +#include "nodes/makefuncs.h" +#include "parser/parse_type.h" +#include "utils/acl.h" +#include "utils/builtins.h" +#include "utils/lsyscache.h" +#include "utils/syscache.h" + + +static void does_not_exist_skipping(ObjectType objtype, + Node *object); +static bool owningrel_does_not_exist_skipping(List *object, + const char **msg, char **name); +static bool schema_does_not_exist_skipping(List *object, + const char **msg, char **name); +static bool type_in_list_does_not_exist_skipping(List *typenames, + const char **msg, char **name); + + +/* + * Drop one or more objects. + * + * We don't currently handle all object types here. Relations, for example, + * require special handling, because (for example) indexes have additional + * locking requirements. + * + * We look up all the objects first, and then delete them in a single + * performMultipleDeletions() call. This avoids unnecessary DROP RESTRICT + * errors if there are dependencies between them. + */ +void +RemoveObjects(DropStmt *stmt) +{ + ObjectAddresses *objects; + ListCell *cell1; + + objects = new_object_addresses(); + + foreach(cell1, stmt->objects) + { + ObjectAddress address; + Node *object = lfirst(cell1); + Relation relation = NULL; + Oid namespaceId; + + /* Get an ObjectAddress for the object. */ + address = get_object_address(stmt->removeType, + object, + &relation, + AccessExclusiveLock, + stmt->missing_ok); + + /* + * Issue NOTICE if supplied object was not found. Note this is only + * relevant in the missing_ok case, because otherwise + * get_object_address would have thrown an error. + */ + if (!OidIsValid(address.objectId)) + { + Assert(stmt->missing_ok); + does_not_exist_skipping(stmt->removeType, object); + continue; + } + + /* + * Although COMMENT ON FUNCTION, SECURITY LABEL ON FUNCTION, etc. are + * happy to operate on an aggregate as on any other function, we have + * historically not allowed this for DROP FUNCTION. + */ + if (stmt->removeType == OBJECT_FUNCTION) + { + if (get_func_prokind(address.objectId) == PROKIND_AGGREGATE) + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg("\"%s\" is an aggregate function", + NameListToString(castNode(ObjectWithArgs, object)->objname)), + errhint("Use DROP AGGREGATE to drop aggregate functions."))); + } + + /* Check permissions. */ + namespaceId = get_object_namespace(&address); + if (!OidIsValid(namespaceId) || + !pg_namespace_ownercheck(namespaceId, GetUserId())) + check_object_ownership(GetUserId(), stmt->removeType, address, + object, relation); + + /* + * Make note if a temporary namespace has been accessed in this + * transaction. + */ + if (OidIsValid(namespaceId) && isTempNamespace(namespaceId)) + MyXactFlags |= XACT_FLAGS_ACCESSEDTEMPNAMESPACE; + + /* Release any relcache reference count, but keep lock until commit. */ + if (relation) + table_close(relation, NoLock); + + add_exact_object_address(&address, objects); + } + + /* Here we really delete them. */ + performMultipleDeletions(objects, stmt->behavior, 0); + + free_object_addresses(objects); +} + +/* + * owningrel_does_not_exist_skipping + * Subroutine for RemoveObjects + * + * After determining that a specification for a rule or trigger returns that + * the specified object does not exist, test whether its owning relation, and + * its schema, exist or not; if they do, return false --- the trigger or rule + * itself is missing instead. If the owning relation or its schema do not + * exist, fill the error message format string and name, and return true. + */ +static bool +owningrel_does_not_exist_skipping(List *object, const char **msg, char **name) +{ + List *parent_object; + RangeVar *parent_rel; + + parent_object = list_truncate(list_copy(object), + list_length(object) - 1); + + if (schema_does_not_exist_skipping(parent_object, msg, name)) + return true; + + parent_rel = makeRangeVarFromNameList(parent_object); + + if (!OidIsValid(RangeVarGetRelid(parent_rel, NoLock, true))) + { + *msg = gettext_noop("relation \"%s\" does not exist, skipping"); + *name = NameListToString(parent_object); + + return true; + } + + return false; +} + +/* + * schema_does_not_exist_skipping + * Subroutine for RemoveObjects + * + * After determining that a specification for a schema-qualifiable object + * refers to an object that does not exist, test whether the specified schema + * exists or not. If no schema was specified, or if the schema does exist, + * return false -- the object itself is missing instead. If the specified + * schema does not exist, fill the error message format string and the + * specified schema name, and return true. + */ +static bool +schema_does_not_exist_skipping(List *object, const char **msg, char **name) +{ + RangeVar *rel; + + rel = makeRangeVarFromNameList(object); + + if (rel->schemaname != NULL && + !OidIsValid(LookupNamespaceNoError(rel->schemaname))) + { + *msg = gettext_noop("schema \"%s\" does not exist, skipping"); + *name = rel->schemaname; + + return true; + } + + return false; +} + +/* + * type_in_list_does_not_exist_skipping + * Subroutine for RemoveObjects + * + * After determining that a specification for a function, cast, aggregate or + * operator returns that the specified object does not exist, test whether the + * involved datatypes, and their schemas, exist or not; if they do, return + * false --- the original object itself is missing instead. If the datatypes + * or schemas do not exist, fill the error message format string and the + * missing name, and return true. + * + * First parameter is a list of TypeNames. + */ +static bool +type_in_list_does_not_exist_skipping(List *typenames, const char **msg, + char **name) +{ + ListCell *l; + + foreach(l, typenames) + { + TypeName *typeName = lfirst_node(TypeName, l); + + if (typeName != NULL) + { + if (!OidIsValid(LookupTypeNameOid(NULL, typeName, true))) + { + /* type doesn't exist, try to find why */ + if (schema_does_not_exist_skipping(typeName->names, msg, name)) + return true; + + *msg = gettext_noop("type \"%s\" does not exist, skipping"); + *name = TypeNameToString(typeName); + + return true; + } + } + } + + return false; +} + +/* + * does_not_exist_skipping + * Subroutine for RemoveObjects + * + * Generate a NOTICE stating that the named object was not found, and is + * being skipped. This is only relevant when "IF EXISTS" is used; otherwise, + * get_object_address() in RemoveObjects would have thrown an ERROR. + */ +static void +does_not_exist_skipping(ObjectType objtype, Node *object) +{ + const char *msg = NULL; + char *name = NULL; + char *args = NULL; + + switch (objtype) + { + case OBJECT_ACCESS_METHOD: + msg = gettext_noop("access method \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_TYPE: + case OBJECT_DOMAIN: + { + TypeName *typ = castNode(TypeName, object); + + if (!schema_does_not_exist_skipping(typ->names, &msg, &name)) + { + msg = gettext_noop("type \"%s\" does not exist, skipping"); + name = TypeNameToString(typ); + } + } + break; + case OBJECT_COLLATION: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("collation \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_CONVERSION: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("conversion \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_SCHEMA: + msg = gettext_noop("schema \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_STATISTIC_EXT: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("statistics object \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_TSPARSER: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("text search parser \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_TSDICTIONARY: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("text search dictionary \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_TSTEMPLATE: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("text search template \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_TSCONFIGURATION: + if (!schema_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("text search configuration \"%s\" does not exist, skipping"); + name = NameListToString(castNode(List, object)); + } + break; + case OBJECT_EXTENSION: + msg = gettext_noop("extension \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_FUNCTION: + { + ObjectWithArgs *owa = castNode(ObjectWithArgs, object); + + if (!schema_does_not_exist_skipping(owa->objname, &msg, &name) && + !type_in_list_does_not_exist_skipping(owa->objargs, &msg, &name)) + { + msg = gettext_noop("function %s(%s) does not exist, skipping"); + name = NameListToString(owa->objname); + args = TypeNameListToString(owa->objargs); + } + break; + } + case OBJECT_PROCEDURE: + { + ObjectWithArgs *owa = castNode(ObjectWithArgs, object); + + if (!schema_does_not_exist_skipping(owa->objname, &msg, &name) && + !type_in_list_does_not_exist_skipping(owa->objargs, &msg, &name)) + { + msg = gettext_noop("procedure %s(%s) does not exist, skipping"); + name = NameListToString(owa->objname); + args = TypeNameListToString(owa->objargs); + } + break; + } + case OBJECT_ROUTINE: + { + ObjectWithArgs *owa = castNode(ObjectWithArgs, object); + + if (!schema_does_not_exist_skipping(owa->objname, &msg, &name) && + !type_in_list_does_not_exist_skipping(owa->objargs, &msg, &name)) + { + msg = gettext_noop("routine %s(%s) does not exist, skipping"); + name = NameListToString(owa->objname); + args = TypeNameListToString(owa->objargs); + } + break; + } + case OBJECT_AGGREGATE: + { + ObjectWithArgs *owa = castNode(ObjectWithArgs, object); + + if (!schema_does_not_exist_skipping(owa->objname, &msg, &name) && + !type_in_list_does_not_exist_skipping(owa->objargs, &msg, &name)) + { + msg = gettext_noop("aggregate %s(%s) does not exist, skipping"); + name = NameListToString(owa->objname); + args = TypeNameListToString(owa->objargs); + } + break; + } + case OBJECT_OPERATOR: + { + ObjectWithArgs *owa = castNode(ObjectWithArgs, object); + + if (!schema_does_not_exist_skipping(owa->objname, &msg, &name) && + !type_in_list_does_not_exist_skipping(owa->objargs, &msg, &name)) + { + msg = gettext_noop("operator %s does not exist, skipping"); + name = NameListToString(owa->objname); + } + break; + } + case OBJECT_LANGUAGE: + msg = gettext_noop("language \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_CAST: + { + if (!type_in_list_does_not_exist_skipping(list_make1(linitial(castNode(List, object))), &msg, &name) && + !type_in_list_does_not_exist_skipping(list_make1(lsecond(castNode(List, object))), &msg, &name)) + { + /* XXX quote or no quote? */ + msg = gettext_noop("cast from type %s to type %s does not exist, skipping"); + name = TypeNameToString(linitial_node(TypeName, castNode(List, object))); + args = TypeNameToString(lsecond_node(TypeName, castNode(List, object))); + } + } + break; + case OBJECT_TRANSFORM: + if (!type_in_list_does_not_exist_skipping(list_make1(linitial(castNode(List, object))), &msg, &name)) + { + msg = gettext_noop("transform for type %s language \"%s\" does not exist, skipping"); + name = TypeNameToString(linitial_node(TypeName, castNode(List, object))); + args = strVal(lsecond(castNode(List, object))); + } + break; + case OBJECT_TRIGGER: + if (!owningrel_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("trigger \"%s\" for relation \"%s\" does not exist, skipping"); + name = strVal(llast(castNode(List, object))); + args = NameListToString(list_truncate(list_copy(castNode(List, object)), + list_length(castNode(List, object)) - 1)); + } + break; + case OBJECT_POLICY: + if (!owningrel_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("policy \"%s\" for relation \"%s\" does not exist, skipping"); + name = strVal(llast(castNode(List, object))); + args = NameListToString(list_truncate(list_copy(castNode(List, object)), + list_length(castNode(List, object)) - 1)); + } + break; + case OBJECT_EVENT_TRIGGER: + msg = gettext_noop("event trigger \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_RULE: + if (!owningrel_does_not_exist_skipping(castNode(List, object), &msg, &name)) + { + msg = gettext_noop("rule \"%s\" for relation \"%s\" does not exist, skipping"); + name = strVal(llast(castNode(List, object))); + args = NameListToString(list_truncate(list_copy(castNode(List, object)), + list_length(castNode(List, object)) - 1)); + } + break; + case OBJECT_FDW: + msg = gettext_noop("foreign-data wrapper \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_FOREIGN_SERVER: + msg = gettext_noop("server \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + case OBJECT_OPCLASS: + { + List *opcname = list_copy_tail(castNode(List, object), 1); + + if (!schema_does_not_exist_skipping(opcname, &msg, &name)) + { + msg = gettext_noop("operator class \"%s\" does not exist for access method \"%s\", skipping"); + name = NameListToString(opcname); + args = strVal(linitial(castNode(List, object))); + } + } + break; + case OBJECT_OPFAMILY: + { + List *opfname = list_copy_tail(castNode(List, object), 1); + + if (!schema_does_not_exist_skipping(opfname, &msg, &name)) + { + msg = gettext_noop("operator family \"%s\" does not exist for access method \"%s\", skipping"); + name = NameListToString(opfname); + args = strVal(linitial(castNode(List, object))); + } + } + break; + case OBJECT_PUBLICATION: + msg = gettext_noop("publication \"%s\" does not exist, skipping"); + name = strVal((Value *) object); + break; + default: + elog(ERROR, "unrecognized object type: %d", (int) objtype); + break; + } + + if (!args) + ereport(NOTICE, (errmsg(msg, name))); + else + ereport(NOTICE, (errmsg(msg, name, args))); +} |