Fix assorted missing infrastructure for ON CONFLICT.

subquery_planner() failed to apply expression preprocessing to the
arbiterElems and arbiterWhere fields of an OnConflictExpr.  No doubt the
theory was that this wasn't necessary because we don't actually try to
execute those expressions; but that's wrong, because it results in failure
to match to index expressions or index predicates that are changed at all
by preprocessing.  Per bug #14132 from Reynold Smith.

Also add pullup_replace_vars processing for onConflictWhere.  Perhaps
it's impossible to have a subquery reference there, but I'm not exactly
convinced; and even if true today it's a failure waiting to happen.

Also add some comments to other places where one or another field of
OnConflictExpr is intentionally ignored, with explanation as to why it's
okay to do so.

Also, catalog/dependency.c failed to record any dependency on the named
constraint in ON CONFLICT ON CONSTRAINT, allowing such a constraint to
be dropped while rules exist that depend on it, and allowing pg_dump to
dump such a rule before the constraint it refers to.  The normal execution
path managed to error out reasonably for a dangling constraint reference,
but ruleutils.c dumped core; so in addition to fixing the omission, add
a protective check in ruleutils.c, since we can't retroactively add a
dependency in existing databases.

Back-patch to 9.5 where this code was introduced.

Report: <20160510190350.2608.48667@wrigleys.postgresql.org>

diff --git a/src/backend/catalog/dependency.c b/src/backend/catalog/dependency.c
index efca34c66d78fc8efa94f918f45c4b821816a2df..4539c1828eef0ab66f52684be1152b37004167d7 100644 (file)
--- a/src/backend/catalog/dependency.c
+++ b/src/backend/catalog/dependency.c
@@ -1777,6 +1777,15 @@ find_expr_references_walker(Node *node,
        add_object_address(OCLASS_TYPE, cd->resulttype, 0,
                           context->addrs);
    }
+   else if (IsA(node, OnConflictExpr))
+   {
+       OnConflictExpr *onconflict = (OnConflictExpr *) node;
+
+       if (OidIsValid(onconflict->constraint))
+           add_object_address(OCLASS_CONSTRAINT, onconflict->constraint, 0,
+                              context->addrs);
+       /* fall through to examine arguments */
+   }
    else if (IsA(node, SortGroupClause))
    {
        SortGroupClause *sgc = (SortGroupClause *) node;

diff --git a/src/backend/optimizer/plan/planner.c b/src/backend/optimizer/plan/planner.c
index 1fb74ccc15f71381f3db68629aa737d01152495a..fcb57bf411bad57db204773ef82da0e2fee337e6 100644 (file)
--- a/src/backend/optimizer/plan/planner.c
+++ b/src/backend/optimizer/plan/planner.c
@@ -65,6 +65,7 @@ planner_hook_type planner_hook = NULL;
 #define EXPRKIND_APPINFO       7
 #define EXPRKIND_PHV           8
 #define EXPRKIND_TABLESAMPLE   9
+#define EXPRKIND_ARBITER_ELEM  10
 
 /* Passthrough data for standard_qp_callback */
 typedef struct
@@ -483,13 +484,23 @@ subquery_planner(PlannerGlobal *glob, Query *parse,
 
    if (parse->onConflict)
    {
+       parse->onConflict->arbiterElems = (List *)
+           preprocess_expression(root,
+                                 (Node *) parse->onConflict->arbiterElems,
+                                 EXPRKIND_ARBITER_ELEM);
+       parse->onConflict->arbiterWhere =
+           preprocess_expression(root,
+                                 parse->onConflict->arbiterWhere,
+                                 EXPRKIND_QUAL);
        parse->onConflict->onConflictSet = (List *)
-           preprocess_expression(root, (Node *) parse->onConflict->onConflictSet,
+           preprocess_expression(root,
+                                 (Node *) parse->onConflict->onConflictSet,
                                  EXPRKIND_TARGET);
-
        parse->onConflict->onConflictWhere =
-           preprocess_expression(root, (Node *) parse->onConflict->onConflictWhere,
+           preprocess_expression(root,
+                                 parse->onConflict->onConflictWhere,
                                  EXPRKIND_QUAL);
+       /* exclRelTlist contains only Vars, so no preprocessing needed */
    }
 
    root->append_rel_list = (List *)

diff --git a/src/backend/optimizer/plan/subselect.c b/src/backend/optimizer/plan/subselect.c
index 00fb6376d97946e4ccf2ccabc18e681582776460..979802f70d565ba6af6fac31cdf2c3052512b431 100644 (file)
--- a/src/backend/optimizer/plan/subselect.c
+++ b/src/backend/optimizer/plan/subselect.c
@@ -2426,6 +2426,7 @@ finalize_plan(PlannerInfo *root, Plan *plan, Bitmapset *valid_params,
                                  &context);
                finalize_primnode((Node *) mtplan->onConflictWhere,
                                  &context);
+               /* exclRelTlist contains only Vars, doesn't need examination */
                foreach(l, mtplan->plans)
                {
                    context.paramids =

diff --git a/src/backend/optimizer/prep/prepjointree.c b/src/backend/optimizer/prep/prepjointree.c
index 39cce84602441c00d2d53e2cba5abd92bc7e9f15..55fc04d28647cf6131541d0c2aa91ff169c13e0b 100644 (file)
--- a/src/backend/optimizer/prep/prepjointree.c
+++ b/src/backend/optimizer/prep/prepjointree.c
@@ -1031,8 +1031,19 @@ pull_up_simple_subquery(PlannerInfo *root, Node *jtnode, RangeTblEntry *rte,
    parse->returningList = (List *)
        pullup_replace_vars((Node *) parse->returningList, &rvcontext);
    if (parse->onConflict)
+   {
        parse->onConflict->onConflictSet = (List *)
-           pullup_replace_vars((Node *) parse->onConflict->onConflictSet, &rvcontext);
+           pullup_replace_vars((Node *) parse->onConflict->onConflictSet,
+                               &rvcontext);
+       parse->onConflict->onConflictWhere =
+           pullup_replace_vars(parse->onConflict->onConflictWhere,
+                               &rvcontext);
+
+       /*
+        * We assume ON CONFLICT's arbiterElems, arbiterWhere, exclRelTlist
+        * can't contain any references to a subquery
+        */
+   }
    replace_vars_in_jointree((Node *) parse->jointree, &rvcontext,
                             lowest_nulling_outer_join);
    Assert(parse->setOperations == NULL);
@@ -1625,8 +1636,19 @@ pull_up_simple_values(PlannerInfo *root, Node *jtnode, RangeTblEntry *rte)
    parse->returningList = (List *)
        pullup_replace_vars((Node *) parse->returningList, &rvcontext);
    if (parse->onConflict)
+   {
        parse->onConflict->onConflictSet = (List *)
-           pullup_replace_vars((Node *) parse->onConflict->onConflictSet, &rvcontext);
+           pullup_replace_vars((Node *) parse->onConflict->onConflictSet,
+                               &rvcontext);
+       parse->onConflict->onConflictWhere =
+           pullup_replace_vars(parse->onConflict->onConflictWhere,
+                               &rvcontext);
+
+       /*
+        * We assume ON CONFLICT's arbiterElems, arbiterWhere, exclRelTlist
+        * can't contain any references to a subquery
+        */
+   }
    replace_vars_in_jointree((Node *) parse->jointree, &rvcontext, NULL);
    Assert(parse->setOperations == NULL);
    parse->havingQual = pullup_replace_vars(parse->havingQual, &rvcontext);

diff --git a/src/backend/optimizer/util/plancat.c b/src/backend/optimizer/util/plancat.c
index 9442e5fa32b31a236901f376d86fa3bf34d5232d..0d6a1313a08a97ab79bc60a1afe501a64e4da7da 100644 (file)
--- a/src/backend/optimizer/util/plancat.c
+++ b/src/backend/optimizer/util/plancat.c
@@ -530,7 +530,6 @@ infer_arbiter_indexes(PlannerInfo *root)
        Bitmapset  *indexedAttrs = NULL;
        List       *idxExprs;
        List       *predExprs;
-       List       *whereExplicit;
        AttrNumber  natt;
        ListCell   *el;
 
@@ -592,6 +591,7 @@ infer_arbiter_indexes(PlannerInfo *root)
        {
            int         attno = idxRel->rd_index->indkey.values[natt];
 
+           /* XXX broken */
            if (attno < 0)
                elog(ERROR, "system column in index");
 
@@ -652,13 +652,12 @@ infer_arbiter_indexes(PlannerInfo *root)
            goto next;
 
        /*
-        * Any user-supplied ON CONFLICT unique index inference WHERE clause
-        * need only be implied by the cataloged index definitions predicate.
+        * If it's a partial index, its predicate must be implied by the ON
+        * CONFLICT's WHERE clause.
         */
        predExprs = RelationGetIndexPredicate(idxRel);
-       whereExplicit = make_ands_implicit((Expr *) onconflict->arbiterWhere);
 
-       if (!predicate_implied_by(predExprs, whereExplicit))
+       if (!predicate_implied_by(predExprs, (List *) onconflict->arbiterWhere))
            goto next;
 
        results = lappend_oid(results, idxForm->indexrelid);

diff --git a/src/backend/utils/adt/ruleutils.c b/src/backend/utils/adt/ruleutils.c
index 09053d1041d7f4d0abc01221642fe9507d60d72d..922e1733b9464e69387834ae57200e2d52a493b2 100644 (file)
--- a/src/backend/utils/adt/ruleutils.c
+++ b/src/backend/utils/adt/ruleutils.c
@@ -5543,12 +5543,15 @@ get_insert_query_def(Query *query, deparse_context *context)
                context->varprefix = save_varprefix;
            }
        }
-       else if (confl->constraint != InvalidOid)
+       else if (OidIsValid(confl->constraint))
        {
            char       *constraint = get_constraint_name(confl->constraint);
 
+           if (!constraint)
+               elog(ERROR, "cache lookup failed for constraint %u",
+                    confl->constraint);
            appendStringInfo(buf, " ON CONSTRAINT %s",
-                            quote_qualified_identifier(NULL, constraint));
+                            quote_identifier(constraint));
        }
 
        if (confl->action == ONCONFLICT_NOTHING)

diff --git a/src/test/regress/expected/insert_conflict.out b/src/test/regress/expected/insert_conflict.out
index f56cbd642dec667b34b179e6cef5c161a8e2371d..e5c8b4aaacb1ddc59b5cb6bb97e6129e3556e5b2 100644 (file)
--- a/src/test/regress/expected/insert_conflict.out
+++ b/src/test/regress/expected/insert_conflict.out
@@ -454,6 +454,21 @@ ERROR:  column excluded.oid does not exist
 LINE 1: ...values (1) on conflict (key) do update set data = excluded.o...
                                                              ^
 drop table syscolconflicttest;
+--
+-- Previous tests all managed to not test any expressions requiring
+-- planner preprocessing ...
+--
+create table insertconflict (a bigint, b bigint);
+create unique index insertconflicti1 on insertconflict(coalesce(a, 0));
+create unique index insertconflicti2 on insertconflict(b)
+  where coalesce(a, 1) > 0;
+insert into insertconflict values (1, 2)
+on conflict (coalesce(a, 0)) do nothing;
+insert into insertconflict values (1, 2)
+on conflict (b) where coalesce(a, 1) > 0 do nothing;
+insert into insertconflict values (1, 2)
+on conflict (b) where coalesce(a, 1) > 1 do nothing;
+drop table insertconflict;
 -- ******************************************************************
 -- *                                                                *
 -- * Test inheritance (example taken from tutorial)                 *

diff --git a/src/test/regress/sql/insert_conflict.sql b/src/test/regress/sql/insert_conflict.sql
index 8d846f51df4ae2873c832f1a33f1bd2873fc4582..94b1b0aadeebb2d37f961403c8e4e1a6f0a0449e 100644 (file)
--- a/src/test/regress/sql/insert_conflict.sql
+++ b/src/test/regress/sql/insert_conflict.sql
@@ -261,6 +261,28 @@ insert into syscolconflicttest values (1) on conflict (key) do update set data =
 insert into syscolconflicttest values (1) on conflict (key) do update set data = excluded.oid::text;
 drop table syscolconflicttest;
 
+--
+-- Previous tests all managed to not test any expressions requiring
+-- planner preprocessing ...
+--
+create table insertconflict (a bigint, b bigint);
+
+create unique index insertconflicti1 on insertconflict(coalesce(a, 0));
+
+create unique index insertconflicti2 on insertconflict(b)
+  where coalesce(a, 1) > 0;
+
+insert into insertconflict values (1, 2)
+on conflict (coalesce(a, 0)) do nothing;
+
+insert into insertconflict values (1, 2)
+on conflict (b) where coalesce(a, 1) > 0 do nothing;
+
+insert into insertconflict values (1, 2)
+on conflict (b) where coalesce(a, 1) > 1 do nothing;
+
+drop table insertconflict;
+
 
 -- ******************************************************************
 -- *                                                                *