diff options
Diffstat (limited to 'src/backend/executor/nodeSeqscan.c')
| -rw-r--r-- | src/backend/executor/nodeSeqscan.c | 41 |
1 files changed, 37 insertions, 4 deletions
diff --git a/src/backend/executor/nodeSeqscan.c b/src/backend/executor/nodeSeqscan.c index a9da3e769d2..b09b94d82a5 100644 --- a/src/backend/executor/nodeSeqscan.c +++ b/src/backend/executor/nodeSeqscan.c @@ -7,7 +7,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/executor/nodeSeqscan.c,v 1.15 1998/09/25 13:38:32 thomas Exp $ + * $Header: /cvsroot/pgsql/src/backend/executor/nodeSeqscan.c,v 1.16 1999/01/29 09:22:58 vadim Exp $ * *------------------------------------------------------------------------- */ @@ -64,6 +64,34 @@ SeqNext(SeqScan *node) scanstate = node->scanstate; scandesc = scanstate->css_currentScanDesc; direction = estate->es_direction; + slot = scanstate->css_ScanTupleSlot; + + /* + * Check if we are evaluating PlanQual for tuple of this relation. + * Additional checking is not good, but no other way for now. + * We could introduce new nodes for this case and handle + * SeqScan --> NewNode switching in Init/ReScan plan... + */ + if (estate->es_evTuple != NULL && + estate->es_evTuple[node->scanrelid - 1] != NULL) + { + slot->ttc_buffer = InvalidBuffer; + slot->ttc_shouldFree = false; + if (estate->es_evTupleNull[node->scanrelid - 1]) + { + slot->val = NULL; /* must not free tuple! */ + return (slot); + } + slot->val = estate->es_evTuple[node->scanrelid - 1]; + /* + * Note that unlike IndexScan, SeqScan never use keys + * in heap_beginscan (and this is very bad) - so, here + * we have not check are keys ok or not. + */ + /* Flag for the next call that no more tuples */ + estate->es_evTupleNull[node->scanrelid - 1] = true; + return (slot); + } /* ---------------- * get the next tuple from the access methods @@ -79,7 +107,6 @@ SeqNext(SeqScan *node) * be pfree()'d. * ---------------- */ - slot = scanstate->css_ScanTupleSlot; slot = ExecStoreTuple(tuple,/* tuple to store */ slot, /* slot to store in */ @@ -374,9 +401,15 @@ ExecSeqReScan(SeqScan *node, ExprContext *exprCtxt, Plan *parent) outerPlan = outerPlan((Plan *) node); ExecReScan(outerPlan, exprCtxt, parent); } - else + else /* otherwise, we are scanning a relation */ { - /* otherwise, we are scanning a relation */ + /* If this is re-scanning of PlanQual ... */ + if (estate->es_evTuple != NULL && + estate->es_evTuple[node->scanrelid - 1] != NULL) + { + estate->es_evTupleNull[node->scanrelid - 1] = false; + return; + } rel = scanstate->css_currentRelation; scan = scanstate->css_currentScanDesc; direction = estate->es_direction; |