diff options
Diffstat (limited to 'src/backend/optimizer/path/pathkeys.c')
-rw-r--r-- | src/backend/optimizer/path/pathkeys.c | 34 |
1 files changed, 17 insertions, 17 deletions
diff --git a/src/backend/optimizer/path/pathkeys.c b/src/backend/optimizer/path/pathkeys.c index 9179c61cbdb..5d953dfb45a 100644 --- a/src/backend/optimizer/path/pathkeys.c +++ b/src/backend/optimizer/path/pathkeys.c @@ -46,7 +46,7 @@ static bool right_merge_direction(PlannerInfo *root, PathKey *pathkey); * entry if there's not one already. * * Note that this function must not be used until after we have completed - * merging EquivalenceClasses. (We don't try to enforce that here; instead, + * merging EquivalenceClasses. (We don't try to enforce that here; instead, * equivclass.c will complain if a merge occurs after root->canon_pathkeys * has become nonempty.) */ @@ -120,7 +120,7 @@ make_canonical_pathkey(PlannerInfo *root, * * Both the given pathkey and the list members must be canonical for this * to work properly, but that's okay since we no longer ever construct any - * non-canonical pathkeys. (Note: the notion of a pathkey *list* being + * non-canonical pathkeys. (Note: the notion of a pathkey *list* being * canonical includes the additional requirement of no redundant entries, * which is exactly what we are checking for here.) * @@ -162,7 +162,7 @@ pathkey_is_redundant(PathKey *new_pathkey, List *pathkeys) * * If rel is not NULL, it identifies a specific relation we're considering * a path for, and indicates that child EC members for that relation can be - * considered. Otherwise child members are ignored. (See the comments for + * considered. Otherwise child members are ignored. (See the comments for * get_eclass_for_sort_expr.) * * create_it is TRUE if we should create any missing EquivalenceClass @@ -192,7 +192,7 @@ make_pathkey_from_sortinfo(PlannerInfo *root, /* * EquivalenceClasses need to contain opfamily lists based on the family * membership of mergejoinable equality operators, which could belong to - * more than one opfamily. So we have to look up the opfamily's equality + * more than one opfamily. So we have to look up the opfamily's equality * operator and get its membership. */ equality_op = get_opfamily_member(opfamily, @@ -355,7 +355,7 @@ get_cheapest_path_for_pathkeys(List *paths, List *pathkeys, /* * Since cost comparison is a lot cheaper than pathkey comparison, do - * that first. (XXX is that still true?) + * that first. (XXX is that still true?) */ if (matched_path != NULL && compare_path_costs(matched_path, path, cost_criterion) <= 0) @@ -397,7 +397,7 @@ get_cheapest_fractional_path_for_pathkeys(List *paths, /* * Since cost comparison is a lot cheaper than pathkey comparison, do - * that first. (XXX is that still true?) + * that first. (XXX is that still true?) */ if (matched_path != NULL && compare_fractional_path_costs(matched_path, path, fraction) <= 0) @@ -555,7 +555,7 @@ build_expression_pathkey(PlannerInfo *root, /* * convert_subquery_pathkeys * Build a pathkeys list that describes the ordering of a subquery's - * result, in the terms of the outer query. This is essentially a + * result, in the terms of the outer query. This is essentially a * task of conversion. * * 'rel': outer query's RelOptInfo for the subquery relation. @@ -608,7 +608,7 @@ convert_subquery_pathkeys(PlannerInfo *root, RelOptInfo *rel, /* * Note: it might look funny to be setting sortref = 0 for a - * reference to a volatile sub_eclass. However, the + * reference to a volatile sub_eclass. However, the * expression is *not* volatile in the outer query: it's just * a Var referencing whatever the subquery emitted. (IOW, the * outer query isn't going to re-execute the volatile @@ -645,7 +645,7 @@ convert_subquery_pathkeys(PlannerInfo *root, RelOptInfo *rel, /* * Otherwise, the sub_pathkey's EquivalenceClass could contain * multiple elements (representing knowledge that multiple items - * are effectively equal). Each element might match none, one, or + * are effectively equal). Each element might match none, one, or * more of the output columns that are visible to the outer query. * This means we may have multiple possible representations of the * sub_pathkey in the context of the outer query. Ideally we @@ -873,7 +873,7 @@ make_pathkeys_for_sortclauses(PlannerInfo *root, * right sides. * * Note this is called before EC merging is complete, so the links won't - * necessarily point to canonical ECs. Before they are actually used for + * necessarily point to canonical ECs. Before they are actually used for * anything, update_mergeclause_eclasses must be called to ensure that * they've been updated to point to canonical ECs. */ @@ -1007,7 +1007,7 @@ find_mergeclauses_for_pathkeys(PlannerInfo *root, * It's possible that multiple matching clauses might have different * ECs on the other side, in which case the order we put them into our * result makes a difference in the pathkeys required for the other - * input path. However this routine hasn't got any info about which + * input path. However this routine hasn't got any info about which * order would be best, so we don't worry about that. * * It's also possible that the selected mergejoin clauses produce @@ -1038,7 +1038,7 @@ find_mergeclauses_for_pathkeys(PlannerInfo *root, /* * If we didn't find a mergeclause, we're done --- any additional - * sort-key positions in the pathkeys are useless. (But we can still + * sort-key positions in the pathkeys are useless. (But we can still * mergejoin if we found at least one mergeclause.) */ if (matched_restrictinfos == NIL) @@ -1070,7 +1070,7 @@ find_mergeclauses_for_pathkeys(PlannerInfo *root, * Returns a pathkeys list that can be applied to the outer relation. * * Since we assume here that a sort is required, there is no particular use - * in matching any available ordering of the outerrel. (joinpath.c has an + * in matching any available ordering of the outerrel. (joinpath.c has an * entirely separate code path for considering sort-free mergejoins.) Rather, * it's interesting to try to match the requested query_pathkeys so that a * second output sort may be avoided; and failing that, we try to list "more @@ -1401,7 +1401,7 @@ pathkeys_useful_for_merging(PlannerInfo *root, RelOptInfo *rel, List *pathkeys) /* * If we didn't find a mergeclause, we're done --- any additional - * sort-key positions in the pathkeys are useless. (But we can still + * sort-key positions in the pathkeys are useless. (But we can still * mergejoin if we found at least one mergeclause.) */ if (matched) @@ -1431,7 +1431,7 @@ right_merge_direction(PlannerInfo *root, PathKey *pathkey) pathkey->pk_opfamily == query_pathkey->pk_opfamily) { /* - * Found a matching query sort column. Prefer this pathkey's + * Found a matching query sort column. Prefer this pathkey's * direction iff it matches. Note that we ignore pk_nulls_first, * which means that a sort might be needed anyway ... but we still * want to prefer only one of the two possible directions, and we @@ -1507,13 +1507,13 @@ truncate_useless_pathkeys(PlannerInfo *root, * useful according to truncate_useless_pathkeys(). * * This is a cheap test that lets us skip building pathkeys at all in very - * simple queries. It's OK to err in the direction of returning "true" when + * simple queries. It's OK to err in the direction of returning "true" when * there really aren't any usable pathkeys, but erring in the other direction * is bad --- so keep this in sync with the routines above! * * We could make the test more complex, for example checking to see if any of * the joinclauses are really mergejoinable, but that likely wouldn't win - * often enough to repay the extra cycles. Queries with neither a join nor + * often enough to repay the extra cycles. Queries with neither a join nor * a sort are reasonably common, though, so this much work seems worthwhile. */ bool |