From 5bc3f2aeeb4e543055c9e32401328950a6647eb3 Mon Sep 17 00:00:00 2001 From: Bruce Momjian Date: Wed, 24 Apr 2002 02:48:55 +0000 Subject: [PATCH] Attached is a patch for ALTER TRIGGER RENAME per the above thread. I left a stub for a future "ALTER RULE RENAME" but did not write that one yet. Bruce, if you want to add my name for for that I'll take it and do it later. Joe Conway --- src/backend/commands/tablecmds.c | 117 +++++++++++++++++++++++++++++++ src/backend/nodes/copyfuncs.c | 5 +- src/backend/nodes/equalfuncs.c | 4 +- src/backend/parser/gram.y | 15 +++- src/backend/tcop/utility.c | 37 ++++++---- src/include/commands/tablecmds.h | 5 ++ src/include/nodes/parsenodes.h | 16 +++-- 7 files changed, 175 insertions(+), 24 deletions(-) diff --git a/src/backend/commands/tablecmds.c b/src/backend/commands/tablecmds.c index d0cdacc92e..5abe8f129b 100644 --- a/src/backend/commands/tablecmds.c +++ b/src/backend/commands/tablecmds.c @@ -2846,6 +2846,123 @@ renamerel(Oid relid, const char *newrelname) relation_close(targetrelation, NoLock); } +/* + * renametrig - changes the name of a trigger on a relation + * + * trigger name is changed in trigger catalog. + * No record of the previous name is kept. + * + * get proper relrelation from relation catalog (if not arg) + * scan trigger catalog + * for name conflict (within rel) + * for original trigger (if not arg) + * modify tgname in trigger tuple + * insert modified trigger in trigger catalog + * delete original trigger from trigger catalog + */ +extern void renametrig(Oid relid, + const char *oldname, + const char *newname) +{ + Relation targetrel; + Relation tgrel; + HeapTuple tuple; + SysScanDesc tgscan; + ScanKeyData key; + bool found = FALSE; + Relation idescs[Num_pg_trigger_indices]; + + /* + * Grab an exclusive lock on the target table, which we will NOT + * release until end of transaction. + */ + targetrel = heap_open(relid, AccessExclusiveLock); + + /* + * Scan pg_trigger twice for existing triggers on relation. We do this in + * order to ensure a trigger does not exist with newname (The unique index + * on tgrelid/tgname would complain anyway) and to ensure a trigger does + * exist with oldname. + * + * NOTE that this is cool only because we have AccessExclusiveLock on the + * relation, so the trigger set won't be changing underneath us. + */ + tgrel = heap_openr(TriggerRelationName, RowExclusiveLock); + + /* + * First pass -- look for name conflict + */ + ScanKeyEntryInitialize(&key, 0, + Anum_pg_trigger_tgrelid, + F_OIDEQ, + ObjectIdGetDatum(relid)); + tgscan = systable_beginscan(tgrel, TriggerRelidNameIndex, true, + SnapshotNow, 1, &key); + while (HeapTupleIsValid(tuple = systable_getnext(tgscan))) + { + Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple); + + if (namestrcmp(&(pg_trigger->tgname), newname) == 0) + elog(ERROR, "renametrig: trigger %s already defined on relation %s", + newname, RelationGetRelationName(targetrel)); + } + systable_endscan(tgscan); + + /* + * Second pass -- look for trigger existing with oldname and update + */ + ScanKeyEntryInitialize(&key, 0, + Anum_pg_trigger_tgrelid, + F_OIDEQ, + ObjectIdGetDatum(relid)); + tgscan = systable_beginscan(tgrel, TriggerRelidNameIndex, true, + SnapshotNow, 1, &key); + while (HeapTupleIsValid(tuple = systable_getnext(tgscan))) + { + Form_pg_trigger pg_trigger = (Form_pg_trigger) GETSTRUCT(tuple); + + if (namestrcmp(&(pg_trigger->tgname), oldname) == 0) + { + /* + * Update pg_trigger tuple with new tgname. + * (Scribbling on tuple is OK because it's a copy...) + */ + namestrcpy(&(pg_trigger->tgname), newname); + simple_heap_update(tgrel, &tuple->t_self, tuple); + + /* + * keep system catalog indices current + */ + CatalogOpenIndices(Num_pg_trigger_indices, Name_pg_trigger_indices, idescs); + CatalogIndexInsert(idescs, Num_pg_trigger_indices, tgrel, tuple); + CatalogCloseIndices(Num_pg_trigger_indices, idescs); + + /* + * Invalidate relation's relcache entry so that other + * backends (and this one too!) are sent SI message to make them + * rebuild relcache entries. + */ + CacheInvalidateRelcache(relid); + + found = TRUE; + break; + } + } + systable_endscan(tgscan); + + heap_close(tgrel, RowExclusiveLock); + + if (!found) + elog(ERROR, "renametrig: trigger %s not defined on relation %s", + oldname, RelationGetRelationName(targetrel)); + + /* + * Close rel, but keep exclusive lock! + */ + heap_close(targetrel, NoLock); +} + + /* * Given a trigger function OID, determine whether it is an RI trigger, * and if so whether it is attached to PK or FK relation. diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index 8c73b9ecb2..ed48c18da0 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -2137,10 +2137,11 @@ _copyRenameStmt(RenameStmt *from) RenameStmt *newnode = makeNode(RenameStmt); Node_Copy(from, newnode, relation); - if (from->column) - newnode->column = pstrdup(from->column); + if (from->oldname) + newnode->oldname = pstrdup(from->oldname); if (from->newname) newnode->newname = pstrdup(from->newname); + newnode->renameType = from->renameType; return newnode; } diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c index c9f761980b..1ea36c43f1 100644 --- a/src/backend/nodes/equalfuncs.c +++ b/src/backend/nodes/equalfuncs.c @@ -983,10 +983,12 @@ _equalRenameStmt(RenameStmt *a, RenameStmt *b) { if (!equal(a->relation, b->relation)) return false; - if (!equalstr(a->column, b->column)) + if (!equalstr(a->oldname, b->oldname)) return false; if (!equalstr(a->newname, b->newname)) return false; + if (a->renameType != b->renameType) + return false; return true; } diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index 13234c06ee..bcc8db75c1 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -2919,8 +2919,21 @@ RenameStmt: ALTER TABLE relation_expr RENAME opt_column opt_name TO name { RenameStmt *n = makeNode(RenameStmt); n->relation = $3; - n->column = $6; + n->oldname = $6; n->newname = $8; + if ($6 == NULL) + n->renameType = RENAME_TABLE; + else + n->renameType = RENAME_COLUMN; + $$ = (Node *)n; + } + | ALTER TRIGGER name ON relation_expr RENAME TO name + { + RenameStmt *n = makeNode(RenameStmt); + n->relation = $5; + n->oldname = $3; + n->newname = $8; + n->renameType = RENAME_TRIGGER; $$ = (Node *)n; } ; diff --git a/src/backend/tcop/utility.c b/src/backend/tcop/utility.c index cd27865385..6b625c4e17 100644 --- a/src/backend/tcop/utility.c +++ b/src/backend/tcop/utility.c @@ -377,23 +377,30 @@ ProcessUtility(Node *parsetree, CheckOwnership(stmt->relation, true); - if (stmt->column == NULL) + switch (stmt->renameType) { - /* - * rename relation - */ - renamerel(RangeVarGetRelid(stmt->relation, false), - stmt->newname); - } - else - { - /* - * rename attribute - */ - renameatt(RangeVarGetRelid(stmt->relation, false), - stmt->column, /* old att name */ + case RENAME_TABLE: + renamerel(RangeVarGetRelid(stmt->relation, false), + stmt->newname); + break; + case RENAME_COLUMN: + renameatt(RangeVarGetRelid(stmt->relation, false), + stmt->oldname, /* old att name */ stmt->newname, /* new att name */ - interpretInhOption(stmt->relation->inhOpt)); /* recursive? */ + interpretInhOption(stmt->relation->inhOpt)); /* recursive? */ + break; + case RENAME_TRIGGER: + renametrig(RangeVarGetRelid(stmt->relation, false), + stmt->oldname, /* old att name */ + stmt->newname); /* new att name */ + break; + case RENAME_RULE: + elog(ERROR, "ProcessUtility: Invalid target for RENAME: %d", + stmt->renameType); + break; + default: + elog(ERROR, "ProcessUtility: Invalid target for RENAME: %d", + stmt->renameType); } } break; diff --git a/src/include/commands/tablecmds.h b/src/include/commands/tablecmds.h index cb41938241..9bc71f6437 100644 --- a/src/include/commands/tablecmds.h +++ b/src/include/commands/tablecmds.h @@ -15,6 +15,7 @@ #define TABLECMDS_H #include "nodes/parsenodes.h" +#include "utils/inval.h" extern void AlterTableAddColumn(Oid myrelid, bool inherits, ColumnDef *colDef); @@ -60,4 +61,8 @@ extern void renameatt(Oid relid, extern void renamerel(Oid relid, const char *newrelname); +extern void renametrig(Oid relid, + const char *oldname, + const char *newname); + #endif /* TABLECMDS_H */ diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index cdb9e8b29a..42be9031db 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1233,17 +1233,23 @@ typedef struct RemoveOperStmt } RemoveOperStmt; /* ---------------------- - * Alter Table Rename Statement + * Alter Object Rename Statement * ---------------------- + * Currently supports renaming tables, table columns, and triggers. + * If renaming a table, oldname is ignored. */ +#define RENAME_TABLE 110 +#define RENAME_COLUMN 111 +#define RENAME_TRIGGER 112 +#define RENAME_RULE 113 + typedef struct RenameStmt { NodeTag type; - RangeVar *relation; /* relation to be altered */ - char *column; /* if NULL, rename the relation name to - * the new name. Otherwise, rename this - * column name. */ + RangeVar *relation; /* owning relation */ + char *oldname; /* name of rule, trigger, etc */ char *newname; /* the new name */ + int renameType; /* RENAME_TABLE, RENAME_COLUMN, etc */ } RenameStmt; /* ---------------------- -- 2.39.5