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| author | Tom Lane <tgl@sss.pgh.pa.us> | 2016-08-24 14:37:50 -0400 |
|---|---|---|
| committer | Tom Lane <tgl@sss.pgh.pa.us> | 2016-08-24 14:38:12 -0400 |
| commit | 2c00fad2864350508f666da1a2c04e0cbe9cbf58 (patch) | |
| tree | 15c1158e56998cd9f46b10bd5664cf18b6451297 /src/backend/nodes | |
| parent | 5cd3864075622b203d530f1a710818777859304e (diff) | |
| download | postgresql-2c00fad2864350508f666da1a2c04e0cbe9cbf58.tar.gz | |
Fix improper repetition of previous results from a hashed aggregate.
ExecReScanAgg's check for whether it could re-use a previously calculated
hashtable neglected the possibility that the Agg node might reference
PARAM_EXEC Params that are not referenced by its input plan node. That's
okay if the Params are in upper tlist or qual expressions; but if one
appears in aggregate input expressions, then the hashtable contents need
to be recomputed when the Param's value changes.
To avoid unnecessary performance degradation in the case of a Param that
isn't within an aggregate input, add logic to the planner to determine
which Params are within aggregate inputs. This requires a new field in
struct Agg, but fortunately we never write plans to disk, so this isn't
an initdb-forcing change.
Per report from Jeevan Chalke. This has been broken since forever,
so back-patch to all supported branches.
Andrew Gierth, with minor adjustments by me
Report: <CAM2+6=VY8ykfLT5Q8vb9B6EbeBk-NGuLbT6seaQ+Fq4zXvrDcA@mail.gmail.com>
Diffstat (limited to 'src/backend/nodes')
| -rw-r--r-- | src/backend/nodes/copyfuncs.c | 1 | ||||
| -rw-r--r-- | src/backend/nodes/outfuncs.c | 1 | ||||
| -rw-r--r-- | src/backend/nodes/readfuncs.c | 1 |
3 files changed, 3 insertions, 0 deletions
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index c7a06442ba..1877fb45e5 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -877,6 +877,7 @@ _copyAgg(const Agg *from) COPY_POINTER_FIELD(grpOperators, from->numCols * sizeof(Oid)); } COPY_SCALAR_FIELD(numGroups); + COPY_BITMAPSET_FIELD(aggParams); COPY_NODE_FIELD(groupingSets); COPY_NODE_FIELD(chain); diff --git a/src/backend/nodes/outfuncs.c b/src/backend/nodes/outfuncs.c index 50019f4164..29b7712584 100644 --- a/src/backend/nodes/outfuncs.c +++ b/src/backend/nodes/outfuncs.c @@ -716,6 +716,7 @@ _outAgg(StringInfo str, const Agg *node) appendStringInfo(str, " %u", node->grpOperators[i]); WRITE_LONG_FIELD(numGroups); + WRITE_BITMAPSET_FIELD(aggParams); WRITE_NODE_FIELD(groupingSets); WRITE_NODE_FIELD(chain); } diff --git a/src/backend/nodes/readfuncs.c b/src/backend/nodes/readfuncs.c index c83063e219..6f9a81e3e3 100644 --- a/src/backend/nodes/readfuncs.c +++ b/src/backend/nodes/readfuncs.c @@ -2007,6 +2007,7 @@ _readAgg(void) READ_ATTRNUMBER_ARRAY(grpColIdx, local_node->numCols); READ_OID_ARRAY(grpOperators, local_node->numCols); READ_LONG_FIELD(numGroups); + READ_BITMAPSET_FIELD(aggParams); READ_NODE_FIELD(groupingSets); READ_NODE_FIELD(chain); |