diff options
Diffstat (limited to 'src/backend/commands/tablecmds.c')
| -rw-r--r-- | src/backend/commands/tablecmds.c | 223 |
1 files changed, 212 insertions, 11 deletions
diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index 58f0b01b098..7f7102858b1 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.255 2008/05/19 04:14:24 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.256 2008/06/14 18:04:33 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -61,6 +61,7 @@ #include "rewrite/rewriteDefine.h" #include "rewrite/rewriteHandler.h" #include "storage/bufmgr.h" +#include "storage/lmgr.h" #include "storage/smgr.h" #include "utils/acl.h" #include "utils/builtins.h" @@ -168,6 +169,53 @@ typedef struct NewColumnValue ExprState *exprstate; /* execution state */ } NewColumnValue; +/* + * Error-reporting support for RemoveRelations + */ +struct dropmsgstrings +{ + char kind; + int nonexistent_code; + const char *nonexistent_msg; + const char *skipping_msg; + const char *nota_msg; + const char *drophint_msg; +}; + +static const struct dropmsgstrings dropmsgstringarray[] = { + {RELKIND_RELATION, + ERRCODE_UNDEFINED_TABLE, + gettext_noop("table \"%s\" does not exist"), + gettext_noop("table \"%s\" does not exist, skipping"), + gettext_noop("\"%s\" is not a table"), + gettext_noop("Use DROP TABLE to remove a table.")}, + {RELKIND_SEQUENCE, + ERRCODE_UNDEFINED_TABLE, + gettext_noop("sequence \"%s\" does not exist"), + gettext_noop("sequence \"%s\" does not exist, skipping"), + gettext_noop("\"%s\" is not a sequence"), + gettext_noop("Use DROP SEQUENCE to remove a sequence.")}, + {RELKIND_VIEW, + ERRCODE_UNDEFINED_TABLE, + gettext_noop("view \"%s\" does not exist"), + gettext_noop("view \"%s\" does not exist, skipping"), + gettext_noop("\"%s\" is not a view"), + gettext_noop("Use DROP VIEW to remove a view.")}, + {RELKIND_INDEX, + ERRCODE_UNDEFINED_OBJECT, + gettext_noop("index \"%s\" does not exist"), + gettext_noop("index \"%s\" does not exist, skipping"), + gettext_noop("\"%s\" is not an index"), + gettext_noop("Use DROP INDEX to remove an index.")}, + {RELKIND_COMPOSITE_TYPE, + ERRCODE_UNDEFINED_OBJECT, + gettext_noop("type \"%s\" does not exist"), + gettext_noop("type \"%s\" does not exist, skipping"), + gettext_noop("\"%s\" is not a type"), + gettext_noop("Use DROP TYPE to remove a type.")}, + {'\0', 0, NULL, NULL, NULL, NULL} +}; + static void truncate_check_rel(Relation rel); static List *MergeAttributes(List *schema, List *supers, bool istemp, @@ -497,22 +545,175 @@ DefineRelation(CreateStmt *stmt, char relkind) } /* - * RemoveRelation - * Deletes a relation. + * Emit the right error or warning message for a "DROP" command issued on a + * non-existent relation + */ +static void +DropErrorMsgNonExistent(const char *relname, char rightkind, bool missing_ok) +{ + const struct dropmsgstrings *rentry; + + for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++) + { + if (rentry->kind == rightkind) + { + if (!missing_ok) + { + ereport(ERROR, + (errcode(rentry->nonexistent_code), + errmsg(rentry->nonexistent_msg, relname))); + } + else + { + ereport(NOTICE, (errmsg(rentry->skipping_msg, relname))); + break; + } + } + } + + Assert(rentry->kind != '\0'); /* Should be impossible */ +} + +/* + * Emit the right error message for a "DROP" command issued on a + * relation of the wrong type + */ +static void +DropErrorMsgWrongType(const char *relname, char wrongkind, char rightkind) +{ + const struct dropmsgstrings *rentry; + const struct dropmsgstrings *wentry; + + for (rentry = dropmsgstringarray; rentry->kind != '\0'; rentry++) + if (rentry->kind == rightkind) + break; + Assert(rentry->kind != '\0'); + + for (wentry = dropmsgstringarray; wentry->kind != '\0'; wentry++) + if (wentry->kind == wrongkind) + break; + /* wrongkind could be something we don't have in our table... */ + + ereport(ERROR, + (errcode(ERRCODE_WRONG_OBJECT_TYPE), + errmsg(rentry->nota_msg, relname), + (wentry->kind != '\0') ? errhint(wentry->drophint_msg) : 0)); +} + +/* + * RemoveRelations + * Implements DROP TABLE, DROP INDEX, DROP SEQUENCE, DROP VIEW */ void -RemoveRelation(const RangeVar *relation, DropBehavior behavior) +RemoveRelations(DropStmt *drop) { - Oid relOid; - ObjectAddress object; + ObjectAddresses *objects; + char relkind; + ListCell *cell; - relOid = RangeVarGetRelid(relation, false); + /* + * First we identify all the relations, then we delete them in a single + * performMultipleDeletions() call. This is to avoid unwanted + * DROP RESTRICT errors if one of the relations depends on another. + */ - object.classId = RelationRelationId; - object.objectId = relOid; - object.objectSubId = 0; + /* Determine required relkind */ + switch (drop->removeType) + { + case OBJECT_TABLE: + relkind = RELKIND_RELATION; + break; - performDeletion(&object, behavior); + case OBJECT_INDEX: + relkind = RELKIND_INDEX; + break; + + case OBJECT_SEQUENCE: + relkind = RELKIND_SEQUENCE; + break; + + case OBJECT_VIEW: + relkind = RELKIND_VIEW; + break; + + default: + elog(ERROR, "unrecognized drop object type: %d", + (int) drop->removeType); + relkind = 0; /* keep compiler quiet */ + break; + } + + /* Lock and validate each relation; build a list of object addresses */ + objects = new_object_addresses(); + + foreach(cell, drop->objects) + { + RangeVar *rel = makeRangeVarFromNameList((List *) lfirst(cell)); + Oid relOid; + HeapTuple tuple; + Form_pg_class classform; + ObjectAddress obj; + + /* + * These next few steps are a great deal like relation_openrv, but we + * don't bother building a relcache entry since we don't need it. + * + * Check for shared-cache-inval messages before trying to access the + * relation. This is needed to cover the case where the name + * identifies a rel that has been dropped and recreated since the + * start of our transaction: if we don't flush the old syscache entry, + * then we'll latch onto that entry and suffer an error later. + */ + AcceptInvalidationMessages(); + + /* Look up the appropriate relation using namespace search */ + relOid = RangeVarGetRelid(rel, true); + + /* Not there? */ + if (!OidIsValid(relOid)) + { + DropErrorMsgNonExistent(rel->relname, relkind, drop->missing_ok); + continue; + } + + /* Get the lock before trying to fetch the syscache entry */ + LockRelationOid(relOid, AccessExclusiveLock); + + tuple = SearchSysCache(RELOID, + ObjectIdGetDatum(relOid), + 0, 0, 0); + if (!HeapTupleIsValid(tuple)) + elog(ERROR, "cache lookup failed for relation %u", relOid); + classform = (Form_pg_class) GETSTRUCT(tuple); + + if (classform->relkind != relkind) + DropErrorMsgWrongType(rel->relname, classform->relkind, relkind); + + /* Allow DROP to either table owner or schema owner */ + if (!pg_class_ownercheck(relOid, GetUserId()) && + !pg_namespace_ownercheck(classform->relnamespace, GetUserId())) + aclcheck_error(ACLCHECK_NOT_OWNER, ACL_KIND_CLASS, + rel->relname); + + if (!allowSystemTableMods && IsSystemClass(classform)) + ereport(ERROR, + (errcode(ERRCODE_INSUFFICIENT_PRIVILEGE), + errmsg("permission denied: \"%s\" is a system catalog", + rel->relname))); + + /* OK, we're ready to delete this one */ + obj.classId = RelationRelationId; + obj.objectId = relOid; + obj.objectSubId = 0; + + add_exact_object_address(&obj, objects); + + ReleaseSysCache(tuple); + } + + performMultipleDeletions(objects, drop->behavior); + + free_object_addresses(objects); } /* |