diff options
Diffstat (limited to 'src/backend/utils/adt/selfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 39 |
1 files changed, 32 insertions, 7 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index f596220d5a4..28e95a74eed 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -15,7 +15,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.231 2007/03/27 23:21:10 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/utils/adt/selfuncs.c,v 1.232 2007/04/06 22:33:42 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -4992,6 +4992,7 @@ btcostestimate(PG_FUNCTION_ARGS) int indexcol; bool eqQualHere; bool found_saop; + bool found_null_op; double num_sa_scans; ListCell *l; @@ -5016,6 +5017,7 @@ btcostestimate(PG_FUNCTION_ARGS) indexcol = 0; eqQualHere = false; found_saop = false; + found_null_op = false; num_sa_scans = 1; foreach(l, indexQuals) { @@ -5025,6 +5027,7 @@ btcostestimate(PG_FUNCTION_ARGS) *rightop; Oid clause_op; int op_strategy; + bool is_null_op = false; Assert(IsA(rinfo, RestrictInfo)); clause = rinfo->clause; @@ -5051,6 +5054,17 @@ btcostestimate(PG_FUNCTION_ARGS) clause_op = saop->opno; found_saop = true; } + else if (IsA(clause, NullTest)) + { + NullTest *nt = (NullTest *) clause; + + Assert(nt->nulltesttype == IS_NULL); + leftop = (Node *) nt->arg; + rightop = NULL; + clause_op = InvalidOid; + found_null_op = true; + is_null_op = true; + } else { elog(ERROR, "unsupported indexqual type: %d", @@ -5088,11 +5102,20 @@ btcostestimate(PG_FUNCTION_ARGS) break; } } - op_strategy = get_op_opfamily_strategy(clause_op, - index->opfamily[indexcol]); - Assert(op_strategy != 0); /* not a member of opfamily?? */ - if (op_strategy == BTEqualStrategyNumber) + /* check for equality operator */ + if (is_null_op) + { + /* IS NULL is like = for purposes of selectivity determination */ eqQualHere = true; + } + else + { + op_strategy = get_op_opfamily_strategy(clause_op, + index->opfamily[indexcol]); + Assert(op_strategy != 0); /* not a member of opfamily?? */ + if (op_strategy == BTEqualStrategyNumber) + eqQualHere = true; + } /* count up number of SA scans induced by indexBoundQuals only */ if (IsA(clause, ScalarArrayOpExpr)) { @@ -5108,12 +5131,14 @@ btcostestimate(PG_FUNCTION_ARGS) /* * If index is unique and we found an '=' clause for each column, we can * just assume numIndexTuples = 1 and skip the expensive - * clauselist_selectivity calculations. + * clauselist_selectivity calculations. However, a ScalarArrayOp or + * NullTest invalidates that theory, even though it sets eqQualHere. */ if (index->unique && indexcol == index->ncolumns - 1 && eqQualHere && - !found_saop) + !found_saop && + !found_null_op) numIndexTuples = 1.0; else { |