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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2003-02-03 15:07:08 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2003-02-03 15:07:08 +0000 |
| commit | 4cff59d8d540c441fb0c22dfaa517bc25aa5f794 (patch) | |
| tree | 88b4c216d219582904d3d9d6a236bb9468fe148c /src/backend/executor/nodeIndexscan.c | |
| parent | 0d3e36b6687ae601551fb8047c10a68f2d6fb565 (diff) | |
| download | postgresql-4cff59d8d540c441fb0c22dfaa517bc25aa5f794.tar.gz postgresql-4cff59d8d540c441fb0c22dfaa517bc25aa5f794.zip | |
Tweak planner and executor to avoid doing ExecProject() in table scan
nodes where it's not really necessary. In many cases where the scan node
is not the topmost plan node (eg, joins, aggregation), it's possible to
just return the table tuple directly instead of generating an intermediate
projection tuple. In preliminary testing, this reduced the CPU time
needed for 'SELECT COUNT(*) FROM foo' by about 10%.
Diffstat (limited to 'src/backend/executor/nodeIndexscan.c')
| -rw-r--r-- | src/backend/executor/nodeIndexscan.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/src/backend/executor/nodeIndexscan.c b/src/backend/executor/nodeIndexscan.c index ad8680d0ff4..6d95b111c01 100644 --- a/src/backend/executor/nodeIndexscan.c +++ b/src/backend/executor/nodeIndexscan.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.77 2003/01/12 22:01:38 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/executor/nodeIndexscan.c,v 1.78 2003/02/03 15:07:07 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -583,12 +583,6 @@ ExecInitIndexScan(IndexScan *node, EState *estate) ExecInitScanTupleSlot(estate, &indexstate->ss); /* - * Initialize result tuple type and projection info. - */ - ExecAssignResultTypeFromTL(&indexstate->ss.ps); - ExecAssignProjectionInfo(&indexstate->ss.ps); - - /* * Initialize index-specific scan state */ indexstate->iss_NumIndices = 0; @@ -918,6 +912,12 @@ ExecInitIndexScan(IndexScan *node, EState *estate) indexstate->iss_ScanDescs = scanDescs; /* + * Initialize result tuple type and projection info. + */ + ExecAssignResultTypeFromTL(&indexstate->ss.ps); + ExecAssignScanProjectionInfo(&indexstate->ss); + + /* * all done. */ return indexstate; |