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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2003-01-20 18:55:07 +0000 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2003-01-20 18:55:07 +0000 |
| commit | bdfbfde1b168b3332c4cdac34ac86a80aaf4d442 (patch) | |
| tree | f35bf1af04733069f3a6b0a2698ac10dbd6544ed /src/backend/executor/nodeMergejoin.c | |
| parent | be2b660ecd5ca205570825633e7b8479379ddc64 (diff) | |
| download | postgresql-bdfbfde1b168b3332c4cdac34ac86a80aaf4d442.tar.gz postgresql-bdfbfde1b168b3332c4cdac34ac86a80aaf4d442.zip | |
IN clauses appearing at top level of WHERE can now be handled as joins.
There are two implementation techniques: the executor understands a new
JOIN_IN jointype, which emits at most one matching row per left-hand row,
or the result of the IN's sub-select can be fed through a DISTINCT filter
and then joined as an ordinary relation.
Along the way, some minor code cleanup in the optimizer; notably, break
out most of the jointree-rearrangement preprocessing in planner.c and
put it in a new file prep/prepjointree.c.
Diffstat (limited to 'src/backend/executor/nodeMergejoin.c')
| -rw-r--r-- | src/backend/executor/nodeMergejoin.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/src/backend/executor/nodeMergejoin.c b/src/backend/executor/nodeMergejoin.c index af6cd8d6f3f..d5dc7f421aa 100644 --- a/src/backend/executor/nodeMergejoin.c +++ b/src/backend/executor/nodeMergejoin.c @@ -8,7 +8,7 @@ * * * IDENTIFICATION - * $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.55 2002/12/15 16:17:46 tgl Exp $ + * $Header: /cvsroot/pgsql/src/backend/executor/nodeMergejoin.c,v 1.56 2003/01/20 18:54:45 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -381,6 +381,7 @@ ExecMergeJoin(MergeJoinState *node) switch (node->js.jointype) { case JOIN_INNER: + case JOIN_IN: doFillOuter = false; doFillInner = false; break; @@ -581,9 +582,15 @@ ExecMergeJoin(MergeJoinState *node) * the econtext's tuple pointers were set up before * checking the merge qual, so we needn't do it again. */ - qualResult = (joinqual == NIL || - ExecQual(joinqual, econtext, false)); - MJ_DEBUG_QUAL(joinqual, qualResult); + if (node->js.jointype == JOIN_IN && + node->mj_MatchedOuter) + qualResult = false; + else + { + qualResult = (joinqual == NIL || + ExecQual(joinqual, econtext, false)); + MJ_DEBUG_QUAL(joinqual, qualResult); + } if (qualResult) { @@ -1452,6 +1459,7 @@ ExecInitMergeJoin(MergeJoin *node, EState *estate) switch (node->join.jointype) { case JOIN_INNER: + case JOIN_IN: break; case JOIN_LEFT: mergestate->mj_NullInnerTupleSlot = |