diff options
Diffstat (limited to 'src/backend/utils/time/tqual.c')
| -rw-r--r-- | src/backend/utils/time/tqual.c | 64 |
1 files changed, 29 insertions, 35 deletions
diff --git a/src/backend/utils/time/tqual.c b/src/backend/utils/time/tqual.c index f8dcf43b64d..fa6bd4a3c58 100644 --- a/src/backend/utils/time/tqual.c +++ b/src/backend/utils/time/tqual.c @@ -21,7 +21,7 @@ * TransactionIdDidCommit will both return true. If we check only * TransactionIdDidCommit, we could consider a tuple committed when a * later GetSnapshotData call will still think the originating transaction - * is in progress, which leads to application-level inconsistency. The + * is in progress, which leads to application-level inconsistency. The * upshot is that we gotta check TransactionIdIsInProgress first in all * code paths, except for a few cases where we are looking at * subtransactions of our own main transaction and so there can't be any @@ -32,7 +32,7 @@ * Portions Copyright (c) 1994, Regents of the University of California * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.90 2005/08/20 00:39:57 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/time/tqual.c,v 1.91 2005/10/15 02:49:37 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -559,8 +559,7 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid, else if (TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmin(tuple))) { if (HeapTupleHeaderGetCmin(tuple) >= curcid) - return HeapTupleInvisible; /* inserted after scan - * started */ + return HeapTupleInvisible; /* inserted after scan started */ if (tuple->t_infomask & HEAP_XMAX_INVALID) /* xid invalid */ return HeapTupleMayBeUpdated; @@ -581,11 +580,9 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid, Assert(TransactionIdIsCurrentTransactionId(HeapTupleHeaderGetXmax(tuple))); if (HeapTupleHeaderGetCmax(tuple) >= curcid) - return HeapTupleSelfUpdated; /* updated after scan - * started */ + return HeapTupleSelfUpdated; /* updated after scan started */ else - return HeapTupleInvisible; /* updated before scan - * started */ + return HeapTupleInvisible; /* updated before scan started */ } else if (TransactionIdIsInProgress(HeapTupleHeaderGetXmin(tuple))) return HeapTupleInvisible; @@ -632,8 +629,7 @@ HeapTupleSatisfiesUpdate(HeapTupleHeader tuple, CommandId curcid, if (tuple->t_infomask & HEAP_IS_LOCKED) return HeapTupleMayBeUpdated; if (HeapTupleHeaderGetCmax(tuple) >= curcid) - return HeapTupleSelfUpdated; /* updated after scan - * started */ + return HeapTupleSelfUpdated; /* updated after scan started */ else return HeapTupleInvisible; /* updated before scan started */ } @@ -945,12 +941,12 @@ HeapTupleSatisfiesSnapshot(HeapTupleHeader tuple, Snapshot snapshot, * By here, the inserting transaction has committed - have to check * when... * - * Note that the provided snapshot contains only top-level XIDs, so we - * have to convert a subxact XID to its parent for comparison. - * However, we can make first-pass range checks with the given XID, - * because a subxact with XID < xmin has surely also got a parent with - * XID < xmin, while one with XID >= xmax must belong to a parent that - * was not yet committed at the time of this snapshot. + * Note that the provided snapshot contains only top-level XIDs, so we have + * to convert a subxact XID to its parent for comparison. However, we can + * make first-pass range checks with the given XID, because a subxact with + * XID < xmin has surely also got a parent with XID < xmin, while one with + * XID >= xmax must belong to a parent that was not yet committed at the + * time of this snapshot. */ if (TransactionIdFollowsOrEquals(HeapTupleHeaderGetXmin(tuple), snapshot->xmin)) @@ -1074,8 +1070,8 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, /* * Has inserting transaction committed? * - * If the inserting transaction aborted, then the tuple was never visible - * to any other transaction, so we can delete it immediately. + * If the inserting transaction aborted, then the tuple was never visible to + * any other transaction, so we can delete it immediately. */ if (!(tuple->t_infomask & HEAP_XMIN_COMMITTED)) { @@ -1135,8 +1131,7 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, else { /* - * Not in Progress, Not Committed, so either Aborted or - * crashed + * Not in Progress, Not Committed, so either Aborted or crashed */ tuple->t_infomask |= HEAP_XMIN_INVALID; SetBufferCommitInfoNeedsSave(buffer); @@ -1147,8 +1142,8 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, } /* - * Okay, the inserter committed, so it was good at some point. Now - * what about the deleting transaction? + * Okay, the inserter committed, so it was good at some point. Now what + * about the deleting transaction? */ if (tuple->t_infomask & HEAP_XMAX_INVALID) return HEAPTUPLE_LIVE; @@ -1156,10 +1151,10 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, if (tuple->t_infomask & HEAP_IS_LOCKED) { /* - * "Deleting" xact really only locked it, so the tuple - * is live in any case. However, we must make sure that either - * XMAX_COMMITTED or XMAX_INVALID gets set once the xact is gone; - * otherwise it is unsafe to recycle CLOG status after vacuuming. + * "Deleting" xact really only locked it, so the tuple is live in any + * case. However, we must make sure that either XMAX_COMMITTED or + * XMAX_INVALID gets set once the xact is gone; otherwise it is unsafe + * to recycle CLOG status after vacuuming. */ if (!(tuple->t_infomask & HEAP_XMAX_COMMITTED)) { @@ -1175,9 +1170,9 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, } /* - * We don't really care whether xmax did commit, abort or - * crash. We know that xmax did lock the tuple, but - * it did not and will never actually update it. + * We don't really care whether xmax did commit, abort or crash. + * We know that xmax did lock the tuple, but it did not and will + * never actually update it. */ tuple->t_infomask |= HEAP_XMAX_INVALID; SetBufferCommitInfoNeedsSave(buffer); @@ -1204,8 +1199,7 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, else { /* - * Not in Progress, Not Committed, so either Aborted or - * crashed + * Not in Progress, Not Committed, so either Aborted or crashed */ tuple->t_infomask |= HEAP_XMAX_INVALID; SetBufferCommitInfoNeedsSave(buffer); @@ -1223,10 +1217,10 @@ HeapTupleSatisfiesVacuum(HeapTupleHeader tuple, TransactionId OldestXmin, HeapTupleHeaderGetXmax(tuple))) { /* - * 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. + * 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. */ if (!(tuple->t_infomask & HEAP_UPDATED)) return HEAPTUPLE_DEAD; |