diff options
Diffstat (limited to 'src/backend/access/gist/gistscan.c')
| -rw-r--r-- | src/backend/access/gist/gistscan.c | 16 |
1 files changed, 16 insertions, 0 deletions
diff --git a/src/backend/access/gist/gistscan.c b/src/backend/access/gist/gistscan.c index 099849a606b..d0fea2b86ce 100644 --- a/src/backend/access/gist/gistscan.c +++ b/src/backend/access/gist/gistscan.c @@ -17,6 +17,7 @@ #include "access/gist_private.h" #include "access/gistscan.h" #include "access/relscan.h" +#include "utils/lsyscache.h" #include "utils/memutils.h" #include "utils/rel.h" @@ -263,6 +264,8 @@ gistrescan(PG_FUNCTION_ARGS) memmove(scan->orderByData, orderbys, scan->numberOfOrderBys * sizeof(ScanKeyData)); + so->orderByTypes = (Oid *) palloc(scan->numberOfOrderBys * sizeof(Oid)); + /* * Modify the order-by key so that the Distance method is called for * all comparisons. The original operator is passed to the Distance @@ -281,6 +284,19 @@ gistrescan(PG_FUNCTION_ARGS) GIST_DISTANCE_PROC, skey->sk_attno, RelationGetRelationName(scan->indexRelation)); + /* + * Look up the datatype returned by the original ordering operator. + * GiST always uses a float8 for the distance function, but the + * ordering operator could be anything else. + * + * XXX: The distance function is only allowed to be lossy if the + * ordering operator's result type is float4 or float8. Otherwise + * we don't know how to return the distance to the executor. But + * we cannot check that here, as we won't know if the distance + * function is lossy until it returns *recheck = true for the + * first time. + */ + so->orderByTypes[i] = get_func_rettype(skey->sk_func.fn_oid); fmgr_info_copy(&(skey->sk_func), finfo, so->giststate->scanCxt); /* Restore prior fn_extra pointers, if not first time */ |