diff options
| -rw-r--r-- | src/backend/executor/execIndexing.c | 133 |
1 files changed, 5 insertions, 128 deletions
diff --git a/src/backend/executor/execIndexing.c b/src/backend/executor/execIndexing.c index afe7ce87d4c..74becdc85df 100644 --- a/src/backend/executor/execIndexing.c +++ b/src/backend/executor/execIndexing.c @@ -136,11 +136,6 @@ static bool check_exclusion_or_unique_constraint(Relation heap, Relation index, static bool index_recheck_constraint(Relation index, Oid *constr_procs, Datum *existing_values, bool *existing_isnull, Datum *new_values); -static bool index_unchanged_by_update(ResultRelInfo *resultRelInfo, - EState *estate, IndexInfo *indexInfo, - Relation indexRelation); -static bool index_expression_changed_walker(Node *node, - Bitmapset *allUpdatedCols); /* ---------------------------------------------------------------- * ExecOpenIndices @@ -406,11 +401,12 @@ ExecInsertIndexTuples(ResultRelInfo *resultRelInfo, * There's definitely going to be an index_insert() call for this * index. If we're being called as part of an UPDATE statement, * consider if the 'indexUnchanged' = true hint should be passed. + * + * XXX We always assume that the hint should be passed for an UPDATE. + * This is a workaround for a bug in PostgreSQL 14. In practice this + * won't make much difference for current users of the hint. */ - indexUnchanged = update && index_unchanged_by_update(resultRelInfo, - estate, - indexInfo, - indexRelation); + indexUnchanged = update; satisfiesConstraint = index_insert(indexRelation, /* index relation */ @@ -923,122 +919,3 @@ index_recheck_constraint(Relation index, Oid *constr_procs, return true; } - -/* - * Check if ExecInsertIndexTuples() should pass indexUnchanged hint. - * - * When the executor performs an UPDATE that requires a new round of index - * tuples, determine if we should pass 'indexUnchanged' = true hint for one - * single index. - */ -static bool -index_unchanged_by_update(ResultRelInfo *resultRelInfo, EState *estate, - IndexInfo *indexInfo, Relation indexRelation) -{ - Bitmapset *updatedCols = ExecGetUpdatedCols(resultRelInfo, estate); - Bitmapset *extraUpdatedCols = ExecGetExtraUpdatedCols(resultRelInfo, estate); - Bitmapset *allUpdatedCols; - bool hasexpression = false; - List *idxExprs; - - /* - * Check for indexed attribute overlap with updated columns. - * - * Only do this for key columns. A change to a non-key column within an - * INCLUDE index should not be counted here. Non-key column values are - * opaque payload state to the index AM, a little like an extra table TID. - */ - for (int attr = 0; attr < indexInfo->ii_NumIndexKeyAttrs; attr++) - { - int keycol = indexInfo->ii_IndexAttrNumbers[attr]; - - if (keycol <= 0) - { - /* - * Skip expressions for now, but remember to deal with them later - * on - */ - hasexpression = true; - continue; - } - - if (bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber, - updatedCols) || - bms_is_member(keycol - FirstLowInvalidHeapAttributeNumber, - extraUpdatedCols)) - { - /* Changed key column -- don't hint for this index */ - return false; - } - } - - /* - * When we get this far and index has no expressions, return true so that - * index_insert() call will go on to pass 'indexUnchanged' = true hint. - * - * The _absence_ of an indexed key attribute that overlaps with updated - * attributes (in addition to the total absence of indexed expressions) - * shows that the index as a whole is logically unchanged by UPDATE. - */ - if (!hasexpression) - return true; - - /* - * Need to pass only one bms to expression_tree_walker helper function. - * Avoid allocating memory in common case where there are no extra cols. - */ - if (!extraUpdatedCols) - allUpdatedCols = updatedCols; - else - allUpdatedCols = bms_union(updatedCols, extraUpdatedCols); - - /* - * We have to work slightly harder in the event of indexed expressions, - * but the principle is the same as before: try to find columns (Vars, - * actually) that overlap with known-updated columns. - * - * If we find any matching Vars, don't pass hint for index. Otherwise - * pass hint. - */ - idxExprs = RelationGetIndexExpressions(indexRelation); - hasexpression = index_expression_changed_walker((Node *) idxExprs, - allUpdatedCols); - list_free(idxExprs); - if (extraUpdatedCols) - bms_free(allUpdatedCols); - - if (hasexpression) - return false; - - return true; -} - -/* - * Indexed expression helper for index_unchanged_by_update(). - * - * Returns true when Var that appears within allUpdatedCols located. - */ -static bool -index_expression_changed_walker(Node *node, Bitmapset *allUpdatedCols) -{ - if (node == NULL) - return false; - - if (IsA(node, Var)) - { - Var *var = (Var *) node; - - if (bms_is_member(var->varattno - FirstLowInvalidHeapAttributeNumber, - allUpdatedCols)) - { - /* Var was updated -- indicates that we should not hint */ - return true; - } - - /* Still haven't found a reason to not pass the hint */ - return false; - } - - return expression_tree_walker(node, index_expression_changed_walker, - (void *) allUpdatedCols); -} |