diff options
Diffstat (limited to 'src/backend/optimizer/path/indxpath.c')
| -rw-r--r-- | src/backend/optimizer/path/indxpath.c | 44 |
1 files changed, 19 insertions, 25 deletions
diff --git a/src/backend/optimizer/path/indxpath.c b/src/backend/optimizer/path/indxpath.c index 1d744978289..f186b89db44 100644 --- a/src/backend/optimizer/path/indxpath.c +++ b/src/backend/optimizer/path/indxpath.c @@ -9,7 +9,7 @@ * * * IDENTIFICATION - * $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.189 2005/09/22 23:25:07 tgl Exp $ + * $PostgreSQL: pgsql/src/backend/optimizer/path/indxpath.c,v 1.190 2005/09/24 22:54:36 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -65,10 +65,9 @@ static bool matches_any_index(RestrictInfo *rinfo, RelOptInfo *rel, Relids outer_relids); static List *find_clauses_for_join(PlannerInfo *root, RelOptInfo *rel, Relids outer_relids, bool isouterjoin); -static bool match_variant_ordering(PlannerInfo *root, - IndexOptInfo *index, - List *restrictclauses, - ScanDirection *indexscandir); +static ScanDirection match_variant_ordering(PlannerInfo *root, + IndexOptInfo *index, + List *restrictclauses); static List *identify_ignorable_ordering_cols(PlannerInfo *root, IndexOptInfo *index, List *restrictclauses); @@ -362,15 +361,15 @@ find_usable_indexes(PlannerInfo *root, RelOptInfo *rel, root->query_pathkeys != NIL && pathkeys_useful_for_ordering(root, useful_pathkeys) == 0) { - ScanDirection indexscandir; + ScanDirection scandir; - if (match_variant_ordering(root, index, restrictclauses, - &indexscandir)) + scandir = match_variant_ordering(root, index, restrictclauses); + if (!ScanDirectionIsNoMovement(scandir)) { ipath = create_index_path(root, index, restrictclauses, root->query_pathkeys, - indexscandir, + scandir, false); result = lappend(result, ipath); } @@ -1304,15 +1303,14 @@ find_clauses_for_join(PlannerInfo *root, RelOptInfo *rel, * 'restrictclauses' is the list of sublists of restriction clauses * matching the columns of the index (NIL if none) * - * Returns TRUE if able to match the requested query pathkeys, FALSE if not. - * In the TRUE case, sets '*indexscandir' to either ForwardScanDirection or - * BackwardScanDirection to indicate the proper scan direction. + * If able to match the requested query pathkeys, returns either + * ForwardScanDirection or BackwardScanDirection to indicate the proper index + * scan direction. If no match, returns NoMovementScanDirection. */ -static bool +static ScanDirection match_variant_ordering(PlannerInfo *root, IndexOptInfo *index, - List *restrictclauses, - ScanDirection *indexscandir) + List *restrictclauses) { List *ignorables; @@ -1328,7 +1326,7 @@ match_variant_ordering(PlannerInfo *root, * won't cope. */ if (index->relam != BTREE_AM_OID) - return false; + return NoMovementScanDirection; /* * Figure out which index columns can be optionally ignored because * they have an equality constraint. This is the same set for either @@ -1344,17 +1342,13 @@ match_variant_ordering(PlannerInfo *root, if (ignorables && match_index_to_query_keys(root, index, ForwardScanDirection, ignorables)) - { - *indexscandir = ForwardScanDirection; - return true; - } + return ForwardScanDirection; + if (match_index_to_query_keys(root, index, BackwardScanDirection, ignorables)) - { - *indexscandir = BackwardScanDirection; - return true; - } - return false; + return BackwardScanDirection; + + return NoMovementScanDirection; } /* |