diff options
Diffstat (limited to 'src/backend/access/index/genam.c')
| -rw-r--r-- | src/backend/access/index/genam.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/src/backend/access/index/genam.c b/src/backend/access/index/genam.c index 5222966e510..42aaa5bad62 100644 --- a/src/backend/access/index/genam.c +++ b/src/backend/access/index/genam.c @@ -273,6 +273,43 @@ BuildIndexValueDescription(Relation indexRelation, return buf.data; } +/* + * Get the latestRemovedXid from the table entries pointed at by the index + * tuples being deleted. + */ +TransactionId +index_compute_xid_horizon_for_tuples(Relation irel, + Relation hrel, + Buffer ibuf, + OffsetNumber *itemnos, + int nitems) +{ + ItemPointerData *ttids = + (ItemPointerData *) palloc(sizeof(ItemPointerData) * nitems); + TransactionId latestRemovedXid = InvalidTransactionId; + Page ipage = BufferGetPage(ibuf); + IndexTuple itup; + + /* identify what the index tuples about to be deleted point to */ + for (int i = 0; i < nitems; i++) + { + ItemId iitemid; + + iitemid = PageGetItemId(ipage, itemnos[i]); + itup = (IndexTuple) PageGetItem(ipage, iitemid); + + ItemPointerCopy(&itup->t_tid, &ttids[i]); + } + + /* determine the actual xid horizon */ + latestRemovedXid = + table_compute_xid_horizon_for_tuples(hrel, ttids, nitems); + + pfree(ttids); + + return latestRemovedXid; +} + /* ---------------------------------------------------------------- * heap-or-index-scan access to system catalogs |