Router planner: reject SELECT FOR UPDATE ctes

src/backend/distributed/executor/multi_router_executor.c

@@ -272,7 +272,7 @@ AcquireExecutorShardLock(Task *task, CmdType commandType)
 	 * must be conflict with each other modify command. By getting ExlcusiveLock
 	 * we guarantee that. Note that, getting ExlusiveLock does not mimic the
 	 * behaviour of Postgres exactly. Getting row lock with FOR NO KEY UPDATE and
-	 * FOR KEY SHARE do not conflicts in Postgres, yet they block each other in
+	 * FOR KEY SHARE do not conflict in Postgres, yet they block each other in
 	 * our implementation. Since FOR SHARE and FOR KEY SHARE does not conflict
 	 * with each other but conflicts with modify commands, we get ShareLock for
 	 * them.

src/backend/distributed/planner/multi_router_planner.c

@@ -612,6 +612,13 @@ ModifyQuerySupported(Query *queryTree, Query *originalQuery, bool multiShardQuer
 									 NULL, NULL);
 			}
 
+			if (cteQuery->hasForUpdate)
+			{
+				return DeferredError(ERRCODE_FEATURE_NOT_SUPPORTED,
+									 "Router planner doesn't support SELECT FOR UPDATE in common table expressions.",
+									 NULL, NULL);
+			}
+
 			cteError = MultiRouterPlannableQuery(cteQuery);
 			if (cteError)
 			{

src/test/regress/expected/isolation_select_for_update.out

@@ -374,3 +374,28 @@ step s2-finish:
 restore_isolation_tester_func
 
                
+
+starting permutation: s1-begin s1-update-rt-with-cte-select-from-rt s2-begin s2-update-rt s1-finish s2-finish
+step s1-begin: 
+	BEGIN;
+
+step s1-update-rt-with-cte-select-from-rt: 
+	WITH foo AS (SELECT * FROM ref_table FOR UPDATE)
+	UPDATE ref_table SET val_1 = 4 FROM foo WHERE ref_table.id = foo.id;
+
+step s2-begin: 
+	BEGIN;
+
+step s2-update-rt: 
+	UPDATE ref_table SET val_1 = 5 WHERE id = 1;
+ <waiting ...>
+step s1-finish: 
+	COMMIT;
+
+step s2-update-rt: <... completed>
+step s2-finish: 
+	COMMIT;
+
+restore_isolation_tester_func
+
+               

src/test/regress/pg_regress_multi.pl

@@ -111,7 +111,7 @@ GetOptions(
 #
 # XXX: There's some issues with el capitan's SIP here, causing
 # DYLD_LIBRARY_PATH not being inherited if SIP is enabled. That's a
-# know problem, present in postgres itself as well.
+# known problem, present in postgres itself as well.
 if (defined $libdir)
 {
     $ENV{LD_LIBRARY_PATH} = "$libdir:".($ENV{LD_LIBRARY_PATH} || '');

src/test/regress/specs/isolation_select_for_update.spec

@@ -80,6 +80,12 @@ step "s1-select-from-t1-within-cte"
 	SELECT * FROM first_value;
 }
 
+step "s1-update-rt-with-cte-select-from-rt"
+{
+	WITH foo AS (SELECT * FROM ref_table FOR UPDATE)
+	UPDATE ref_table SET val_1 = 4 FROM foo WHERE ref_table.id = foo.id;
+}
+
 step "s1-select-from-t1-with-subquery"
 {
 	SELECT * FROM (SELECT * FROM test_table_1_rf1 FOR UPDATE) foo WHERE id = 1;
@@ -157,3 +163,4 @@ permutation "s1-begin" "s1-select-from-t1-within-cte" "s2-begin" "s2-update-t1"
 permutation "s1-begin" "s1-select-from-t1-with-subquery" "s2-begin" "s2-update-t1" "s1-finish" "s2-finish"
 permutation "s1-begin" "s1-select-from-rt-with-subquery" "s2-begin" "s2-update-rt" "s1-finish" "s2-finish"
 permutation "s1-begin" "s1-select-from-t1-with-view" "s2-begin" "s2-update-t1" "s1-finish" "s2-finish"
+permutation "s1-begin" "s1-update-rt-with-cte-select-from-rt" "s2-begin" "s2-update-rt" "s1-finish" "s2-finish"