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Move renametrig() from tablecmds.c to trigger.c --- if we're going to

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divide backend/commands by object type, let's try to pay at least
minimal attention to respecting that structure, eh?  Also reorder the
contents of tablecmds.c; it seems odd to me to put ALTER commands before
creation/deletion commands.
This commit is contained in:
Tom Lane
2002-04-26 19:29:47 +00:00
parent e90dbd27b1
commit 7de307f96c
5 changed files with 1719 additions and 1724 deletions
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119
src/backend/commands/trigger.c
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@ -7,7 +7,7 @@
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* $Header: /cvsroot/pgsql/src/backend/commands/trigger.c,v 1.114 2002/04/19 16:36:08 tgl Exp $
* $Header: /cvsroot/pgsql/src/backend/commands/trigger.c,v 1.115 2002/04/26 19:29:47 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -503,6 +503,123 @@ RelationRemoveTriggers(Relation rel)
heap_close(tgrel, RowExclusiveLock);
}
/*
* 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
*/
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);
}
/*
* Build trigger data to attach to the given relcache entry.
*