diff options
Diffstat (limited to 'src/backend/utils/time/tqual.c')
| -rw-r--r-- | src/backend/utils/time/tqual.c | 20 |
1 files changed, 11 insertions, 9 deletions
diff --git a/src/backend/utils/time/tqual.c b/src/backend/utils/time/tqual.c index 9463324964..f8dcf43b64 100644 --- a/src/backend/utils/time/tqual.c +++ b/src/backend/utils/time/tqual.c @@ -32,7 +32,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.89 2005/05/19 21:35:47 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.90 2005/08/20 00:39:57 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -677,14 +677,15 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid, * However, we also include the effects of other xacts still in progress. * * Returns extra information in the global variable SnapshotDirty, namely - * xids of concurrent xacts that affected the tuple. Also, the tuple's - * t_ctid (forward link) is returned if it's being updated. + * xids of concurrent xacts that affected the tuple. SnapshotDirty->xmin + * is set to InvalidTransactionId if xmin is either committed good or + * committed dead; or to xmin if that transaction is still in progress. + * Similarly for SnapshotDirty->xmax. */ bool HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer) { SnapshotDirty->xmin = SnapshotDirty->xmax = InvalidTransactionId; - ItemPointerSetInvalid(&(SnapshotDirty->tid)); if (!(tuple->t_infomask & HEAP_XMIN_COMMITTED)) { @@ -781,7 +782,6 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer) { if (tuple->t_infomask & HEAP_IS_LOCKED) return true; - SnapshotDirty->tid = tuple->t_ctid; return false; /* updated by other */ } @@ -824,7 +824,6 @@ HeapTupleSatisfiesDirty(HeapTupleHeader tuple, Buffer buffer) tuple->t_infomask |= HEAP_XMAX_COMMITTED; SetBufferCommitInfoNeedsSave(buffer); - SnapshotDirty->tid = tuple->t_ctid; return false; /* updated by other */ } @@ -1224,10 +1223,13 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, HeapTupleHeaderGetXmax(tuple))) { /* - * inserter also deleted it, so it was never visible to anyone - * else + * Inserter also deleted it, so it was never visible to anyone + * else. However, we can only remove it early if it's not an + * updated tuple; else its parent tuple is linking to it via t_ctid, + * and this tuple mustn't go away before the parent does. */ - return HEAPTUPLE_DEAD; + if (!(tuple->t_infomask & HEAP_UPDATED)) + return HEAPTUPLE_DEAD; } if (!TransactionIdPrecedes(HeapTupleHeaderGetXmax(tuple), OldestXmin)) |