diff options
Diffstat (limited to 'src/backend/utils/adt/selfuncs.c')
| -rw-r--r-- | src/backend/utils/adt/selfuncs.c | 11 |
1 files changed, 11 insertions, 0 deletions
diff --git a/src/backend/utils/adt/selfuncs.c b/src/backend/utils/adt/selfuncs.c index a7a06146a06..23e5526a8e1 100644 --- a/src/backend/utils/adt/selfuncs.c +++ b/src/backend/utils/adt/selfuncs.c @@ -5009,6 +5009,17 @@ get_variable_numdistinct(VariableStatData *vardata, bool *isdefault) */ stadistinct = 2.0; } + else if (vardata->rel && vardata->rel->rtekind == RTE_VALUES) + { + /* + * If the Var represents a column of a VALUES RTE, assume it's unique. + * This could of course be very wrong, but it should tend to be true + * in well-written queries. We could consider examining the VALUES' + * contents to get some real statistics; but that only works if the + * entries are all constants, and it would be pretty expensive anyway. + */ + stadistinct = -1.0; /* unique (and all non null) */ + } else { /* |