diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 20 | ||||
| -rw-r--r-- | src/backend/utils/cache/lsyscache.c | 4 |
2 files changed, 22 insertions, 2 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index d597b7e81fc..e0aeaa69092 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -2261,6 +2261,7 @@ eqjoinsel(PG_FUNCTION_ARGS) Form_pg_statistic stats2 = NULL; bool have_mcvs1 = false; bool have_mcvs2 = false; + bool get_mcv_stats; bool join_is_reversed; RelOptInfo *inner_rel; @@ -2275,11 +2276,25 @@ eqjoinsel(PG_FUNCTION_ARGS) memset(&sslot1, 0, sizeof(sslot1)); memset(&sslot2, 0, sizeof(sslot2)); + /* + * There is no use in fetching one side's MCVs if we lack MCVs for the + * other side, so do a quick check to verify that both stats exist. + */ + get_mcv_stats = (HeapTupleIsValid(vardata1.statsTuple) && + HeapTupleIsValid(vardata2.statsTuple) && + get_attstatsslot(&sslot1, vardata1.statsTuple, + STATISTIC_KIND_MCV, InvalidOid, + 0) && + get_attstatsslot(&sslot2, vardata2.statsTuple, + STATISTIC_KIND_MCV, InvalidOid, + 0)); + if (HeapTupleIsValid(vardata1.statsTuple)) { /* note we allow use of nullfrac regardless of security check */ stats1 = (Form_pg_statistic) GETSTRUCT(vardata1.statsTuple); - if (statistic_proc_security_check(&vardata1, opfuncoid)) + if (get_mcv_stats && + statistic_proc_security_check(&vardata1, opfuncoid)) have_mcvs1 = get_attstatsslot(&sslot1, vardata1.statsTuple, STATISTIC_KIND_MCV, InvalidOid, ATTSTATSSLOT_VALUES | ATTSTATSSLOT_NUMBERS); @@ -2289,7 +2304,8 @@ eqjoinsel(PG_FUNCTION_ARGS) { /* note we allow use of nullfrac regardless of security check */ stats2 = (Form_pg_statistic) GETSTRUCT(vardata2.statsTuple); - if (statistic_proc_security_check(&vardata2, opfuncoid)) + if (get_mcv_stats && + statistic_proc_security_check(&vardata2, opfuncoid)) have_mcvs2 = get_attstatsslot(&sslot2, vardata2.statsTuple, STATISTIC_KIND_MCV, InvalidOid, ATTSTATSSLOT_VALUES | ATTSTATSSLOT_NUMBERS); diff --git a/src/backend/utils/cache/lsyscache.c b/src/backend/utils/cache/lsyscache.c index a16a63f4957..94ca8e12303 100644 --- a/src/backend/utils/cache/lsyscache.c +++ b/src/backend/utils/cache/lsyscache.c @@ -3183,6 +3183,10 @@ get_attavgwidth(Oid relid, AttrNumber attnum) * * If it's desirable to call free_attstatsslot when get_attstatsslot might * not have been called, memset'ing sslot to zeroes will allow that. + * + * Passing flags=0 can be useful to quickly check if the requested slot type + * exists. In this case no arrays are extracted, so free_attstatsslot need + * not be called. */ bool get_attstatsslot(AttStatsSlot *sslot, HeapTuple statstuple, |