BUG#803457: Wrong result with semijoin + view + outer join in maria-5.3-subqueries-mwl90

- Correct handling of outer joins + DuplicateWeedout (docs pending)

mysql-test/r/subselect_sj.result

@@ -1685,4 +1685,34 @@ f10	f10	f11	f10
 0	0	a	0
 0	0	a	0
 drop table t1,t2,t3,t4;
+#
+# BUG#803457: Wrong result with semijoin + view + outer join in maria-5.3-subqueries-mwl90
+#
+set @tmp803457=@@optimizer_switch;
+set optimizer_switch='materialization=off';
+CREATE TABLE t1 (f1 int, f2 int );
+INSERT INTO t1 VALUES (2,0),(4,0),(0,NULL);
+CREATE TABLE t2 (f2 int, f3 int );
+INSERT INTO t2 VALUES (NULL,NULL),(0,0);
+CREATE TABLE t3 ( f1 int, f3 int );
+INSERT INTO t3 VALUES (2,0),(4,0),(0,NULL),(4,0),(8,0);
+CREATE TABLE t4 ( f2 int);
+INSERT INTO t4 VALUES (0),(NULL);
+# The following uses Duplicate Weedout, and "End temporary" must not be
+#   in the middle of the inner side of an outer join:
+explain 
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Start temporary
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	5	Using where
+1	PRIMARY	t4	ALL	NULL	NULL	NULL	NULL	2	Using where; End temporary; Using join buffer (flat, BNL join)
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3 ) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+f1	f2	f3	f3
+2	0	0	0
+4	0	0	0
+4	0	0	0
+0	NULL	NULL	NULL
+DROP TABLE t1, t2, t3, t4;
+set @tmp803457=@@optimizer_switch;
 set optimizer_switch=@subselect_sj_tmp;

mysql-test/r/subselect_sj_jcl6.result

@@ -1696,6 +1696,36 @@ f10	f10	f11	f10
 0	0	a	0
 0	0	a	0
 drop table t1,t2,t3,t4;
+#
+# BUG#803457: Wrong result with semijoin + view + outer join in maria-5.3-subqueries-mwl90
+#
+set @tmp803457=@@optimizer_switch;
+set optimizer_switch='materialization=off';
+CREATE TABLE t1 (f1 int, f2 int );
+INSERT INTO t1 VALUES (2,0),(4,0),(0,NULL);
+CREATE TABLE t2 (f2 int, f3 int );
+INSERT INTO t2 VALUES (NULL,NULL),(0,0);
+CREATE TABLE t3 ( f1 int, f3 int );
+INSERT INTO t3 VALUES (2,0),(4,0),(0,NULL),(4,0),(8,0);
+CREATE TABLE t4 ( f2 int);
+INSERT INTO t4 VALUES (0),(NULL);
+# The following uses Duplicate Weedout, and "End temporary" must not be
+#   in the middle of the inner side of an outer join:
+explain 
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Start temporary
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where; Using join buffer (flat, BNL join)
+1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	5	Using where; Using join buffer (incremental, BNL join)
+1	PRIMARY	t4	ALL	NULL	NULL	NULL	NULL	2	Using where; End temporary; Using join buffer (incremental, BNL join)
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3 ) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+f1	f2	f3	f3
+2	0	0	0
+4	0	0	0
+4	0	0	0
+0	NULL	NULL	NULL
+DROP TABLE t1, t2, t3, t4;
+set @tmp803457=@@optimizer_switch;
 set optimizer_switch=@subselect_sj_tmp;
 #
 # BUG#49129: Wrong result with IN-subquery with join_cache_level=6 and firstmatch=off

mysql-test/t/subselect_sj.test

@@ -1529,5 +1529,31 @@ WHERE t2.f10 IN (
 
 drop table t1,t2,t3,t4;
 
+--echo #
+--echo # BUG#803457: Wrong result with semijoin + view + outer join in maria-5.3-subqueries-mwl90
+--echo #
+set @tmp803457=@@optimizer_switch;
+set optimizer_switch='materialization=off';
+CREATE TABLE t1 (f1 int, f2 int );
+INSERT INTO t1 VALUES (2,0),(4,0),(0,NULL);
+
+CREATE TABLE t2 (f2 int, f3 int );
+INSERT INTO t2 VALUES (NULL,NULL),(0,0);
+
+CREATE TABLE t3 ( f1 int, f3 int );
+INSERT INTO t3 VALUES (2,0),(4,0),(0,NULL),(4,0),(8,0);
+
+CREATE TABLE t4 ( f2 int);
+INSERT INTO t4 VALUES (0),(NULL);
+
+--echo # The following uses Duplicate Weedout, and "End temporary" must not be
+--echo #   in the middle of the inner side of an outer join:
+explain 
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+SELECT * FROM t1 NATURAL LEFT JOIN (t2, t3 ) WHERE IFNULL(t2.f3,'foo') IN (SELECT * FROM t4);
+
+DROP TABLE t1, t2, t3, t4;
+set @tmp803457=@@optimizer_switch;
+
 # The following command must be the last one the file 
 set optimizer_switch=@subselect_sj_tmp;

sql/opt_subselect.cc

@@ -2478,6 +2478,15 @@ void advance_sj_state(JOIN *join, table_map remaining_tables,
                                  nest->nested_join->sj_corr_tables;
     }
     
+    if (pos->dupsweedout_tables)
+    {
+      /* we're in the process of constructing a DuplicateWeedout range */
+      TABLE_LIST *emb= new_join_tab->table->pos_in_table_list->embedding;
+      /* and we've entered an inner side of an outer join*/
+      if (emb && emb->on_expr)
+        pos->dupsweedout_tables |= emb->nested_join->used_tables;
+    }
+
     if (pos->dupsweedout_tables && 
         !(remaining_tables &
           ~new_join_tab->table->map & pos->dupsweedout_tables))