diff options
Diffstat (limited to 'src/backend/commands/cluster.c')
| -rw-r--r-- | src/backend/commands/cluster.c | 56 |
1 files changed, 24 insertions, 32 deletions
diff --git a/src/backend/commands/cluster.c b/src/backend/commands/cluster.c index 6f99a920f5a..d578fc263f0 100644 --- a/src/backend/commands/cluster.c +++ b/src/backend/commands/cluster.c @@ -14,7 +14,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.44 1999/07/17 20:16:51 momjian Exp $ + * $Header: /cvsroot/pgsql/src/backend/commands/cluster.c,v 1.45 1999/09/18 19:06:40 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -101,29 +101,20 @@ cluster(char *oldrelname, char *oldindexname) /* * Like vacuum, cluster spans transactions, so I'm going to handle it - * in the same way. + * in the same way: commit and restart transactions where needed. + * + * We grab exclusive access to the target rel and index for the + * duration of the initial transaction. */ - /* matches the StartTransaction in PostgresMain() */ - - OldHeap = heap_openr(oldrelname); - if (!RelationIsValid(OldHeap)) - { - elog(ERROR, "cluster: unknown relation: \"%s\"", - oldrelname); - } - OIDOldHeap = RelationGetRelid(OldHeap); /* Get OID for the index - * scan */ + OldHeap = heap_openr(oldrelname, AccessExclusiveLock); + OIDOldHeap = RelationGetRelid(OldHeap); OldIndex = index_openr(oldindexname); /* Open old index relation */ - if (!RelationIsValid(OldIndex)) - { - elog(ERROR, "cluster: unknown index: \"%s\"", - oldindexname); - } - OIDOldIndex = RelationGetRelid(OldIndex); /* OID for the index scan */ + LockRelation(OldIndex, AccessExclusiveLock); + OIDOldIndex = RelationGetRelid(OldIndex); - heap_close(OldHeap); + heap_close(OldHeap, NoLock); /* do NOT give up the locks */ index_close(OldIndex); /* @@ -132,7 +123,7 @@ cluster(char *oldrelname, char *oldindexname) * will get the lock after being blocked and add rows which won't be * present in the new table. Bleagh! I'd be best to try and ensure * that no-one's in the tables for the entire duration of this process - * with a pg_vlock. + * with a pg_vlock. XXX Isn't the above comment now invalid? */ NewHeap = copy_heap(OIDOldHeap); OIDNewHeap = RelationGetRelid(NewHeap); @@ -171,7 +162,7 @@ cluster(char *oldrelname, char *oldindexname) renamerel(NewIndexName, saveoldindexname); /* - * Again flush all the buffers. + * Again flush all the buffers. XXX perhaps not needed? */ CommitTransactionCommand(); StartTransactionCommand(); @@ -193,7 +184,7 @@ copy_heap(Oid OIDOldHeap) */ snprintf(NewName, NAMEDATALEN, "temp_%x", OIDOldHeap); - OldHeap = heap_open(OIDOldHeap); + OldHeap = heap_open(OIDOldHeap, AccessExclusiveLock); OldHeapDesc = RelationGetDescr(OldHeap); /* @@ -209,10 +200,11 @@ copy_heap(Oid OIDOldHeap) if (!OidIsValid(OIDNewHeap)) elog(ERROR, "clusterheap: cannot create temporary heap relation\n"); - NewHeap = heap_open(OIDNewHeap); + /* XXX why are we bothering to do this: */ + NewHeap = heap_open(OIDNewHeap, AccessExclusiveLock); - heap_close(NewHeap); - heap_close(OldHeap); + heap_close(NewHeap, AccessExclusiveLock); + heap_close(OldHeap, AccessExclusiveLock); return NewHeap; } @@ -233,7 +225,7 @@ copy_index(Oid OIDOldIndex, Oid OIDNewHeap) int natts; FuncIndexInfo *finfo; - NewHeap = heap_open(OIDNewHeap); + NewHeap = heap_open(OIDNewHeap, AccessExclusiveLock); OldIndex = index_open(OIDOldIndex); /* @@ -305,8 +297,8 @@ copy_index(Oid OIDOldIndex, Oid OIDNewHeap) Old_pg_index_Form->indisunique, Old_pg_index_Form->indisprimary); - heap_close(OldIndex); - heap_close(NewHeap); + index_close(OldIndex); + heap_close(NewHeap, AccessExclusiveLock); } @@ -326,8 +318,8 @@ rebuildheap(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex) * Open the relations I need. Scan through the OldHeap on the OldIndex * and insert each tuple into the NewHeap. */ - LocalNewHeap = (Relation) heap_open(OIDNewHeap); - LocalOldHeap = (Relation) heap_open(OIDOldHeap); + LocalNewHeap = heap_open(OIDNewHeap, AccessExclusiveLock); + LocalOldHeap = heap_open(OIDOldHeap, AccessExclusiveLock); LocalOldIndex = (Relation) index_open(OIDOldIndex); ScanDesc = index_beginscan(LocalOldIndex, false, 0, (ScanKey) NULL); @@ -344,6 +336,6 @@ rebuildheap(Oid OIDNewHeap, Oid OIDOldHeap, Oid OIDOldIndex) index_endscan(ScanDesc); index_close(LocalOldIndex); - heap_close(LocalOldHeap); - heap_close(LocalNewHeap); + heap_close(LocalOldHeap, AccessExclusiveLock); + heap_close(LocalNewHeap, AccessExclusiveLock); } |