MDEV-5107:Left Join Yields All Nulls Instead of Appropriate Matches

MDEV-5034:Wrong result on LEFT JOIN with a SELECT SQ or a merge view, UNION in IN subquery

Make reset null_row same as it was set in evaluate_null_complemented_join_record().

The problem was that view firlds detect null_row by not-yet-reset table.

mysql-test/r/view.result

@@ -4663,6 +4663,52 @@ execute s;
 deallocate prepare s;
 drop view v1;
 drop tables t1,t2;
+#
+# MDEV-5034 (duplicate of MDEV-5107):
+# Left Join Yields All Nulls Instead of Appropriate Matches
+#
+# test #1
+CREATE TABLE t1 (state VARCHAR(32), INDEX(state));
+INSERT INTO t1 VALUES ('Indiana'),('Vermont');
+CREATE TABLE t2 (state VARCHAR(32));
+INSERT INTO t2 VALUES ('Hawaii'),('Oregon'),('Vermont');
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT t1.* FROM t2, t1;
+SELECT * FROM t1 AS outer_t1 LEFT JOIN v1 AS joined_t1
+ON (joined_t1.state = outer_t1.state AND joined_t1.state IN ( SELECT 'Vermont' UNION  SELECT 'Florida' ) );
+state	state
+Indiana	NULL
+Vermont	Vermont
+Vermont	Vermont
+Vermont	Vermont
+SELECT * FROM t1 AS outer_t1 LEFT JOIN (SELECT t1.* FROM t2, t1) AS joined_t1 ON (joined_t1.state = outer_t1.state AND joined_t1.state IN ( SELECT 'Vermont' UNION  SELECT 'Florida' ) );
+state	state
+Indiana	NULL
+Vermont	Vermont
+Vermont	Vermont
+Vermont	Vermont
+drop view v1;
+drop table t1, t2;
+# test #1
+CREATE TABLE t1 (a INT, b VARCHAR(1), INDEX(b,a));
+INSERT INTO t1 VALUES (4,'p'),(1,'q'),(9,'w');
+CREATE TABLE t2 (c VARCHAR(1), INDEX(c));
+INSERT INTO t2 VALUES ('q'),('a');
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT t1a.* FROM t1, t1 AS t1a;
+SELECT * FROM t2 LEFT JOIN v1 ON ( c=b AND a IN ( 1,6 ) );
+c	a	b
+a	NULL	NULL
+q	1	q
+q	1	q
+q	1	q
+CREATE OR REPLACE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT t1a.* FROM t1, t1 AS t1a;
+SELECT * FROM t2 LEFT JOIN v1 ON ( c=b AND a IN ( 1,6 ) );
+c	a	b
+a	NULL	NULL
+q	1	q
+q	1	q
+q	1	q
+drop view v1;
+drop table t1,t2;
 # -----------------------------------------------------------------
 # -- End of 5.3 tests.
 # -----------------------------------------------------------------

mysql-test/t/view.test

@@ -4610,6 +4610,43 @@ deallocate prepare s;
 drop view v1;
 drop tables t1,t2;
 
+--echo #
+--echo # MDEV-5034 (duplicate of MDEV-5107):
+--echo # Left Join Yields All Nulls Instead of Appropriate Matches
+--echo #
+  
+ --echo # test #1
+
+CREATE TABLE t1 (state VARCHAR(32), INDEX(state));
+INSERT INTO t1 VALUES ('Indiana'),('Vermont');
+
+CREATE TABLE t2 (state VARCHAR(32));
+INSERT INTO t2 VALUES ('Hawaii'),('Oregon'),('Vermont');
+
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT t1.* FROM t2, t1;
+SELECT * FROM t1 AS outer_t1 LEFT JOIN v1 AS joined_t1
+ON (joined_t1.state = outer_t1.state AND joined_t1.state IN ( SELECT 'Vermont' UNION  SELECT 'Florida' ) );
+
+SELECT * FROM t1 AS outer_t1 LEFT JOIN (SELECT t1.* FROM t2, t1) AS joined_t1 ON (joined_t1.state = outer_t1.state AND joined_t1.state IN ( SELECT 'Vermont' UNION  SELECT 'Florida' ) );
+
+drop view v1;
+drop table t1, t2;
+
+--echo # test #1
+
+CREATE TABLE t1 (a INT, b VARCHAR(1), INDEX(b,a)); 
+INSERT INTO t1 VALUES (4,'p'),(1,'q'),(9,'w'); 
+
+CREATE TABLE t2 (c VARCHAR(1), INDEX(c)); 
+INSERT INTO t2 VALUES ('q'),('a'); 
+CREATE ALGORITHM=MERGE VIEW v1 AS SELECT t1a.* FROM t1, t1 AS t1a; 
+SELECT * FROM t2 LEFT JOIN v1 ON ( c=b AND a IN ( 1,6 ) ); 
+CREATE OR REPLACE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT t1a.* FROM t1, t1 AS t1a; 
+SELECT * FROM t2 LEFT JOIN v1 ON ( c=b AND a IN ( 1,6 ) );
+
+drop view v1;
+drop table t1,t2;
+
 --echo # -----------------------------------------------------------------
 --echo # -- End of 5.3 tests.
 --echo # -----------------------------------------------------------------

sql/sql_select.cc

@@ -16132,7 +16132,15 @@ sub_select(JOIN *join,JOIN_TAB *join_tab,bool end_of_records)
 {
   DBUG_ENTER("sub_select");
 
-  join_tab->table->null_row=0;
+  if (join_tab->last_inner)
+  {
+    JOIN_TAB *last_inner_tab= join_tab->last_inner;
+    for (JOIN_TAB  *jt= join_tab; jt <= last_inner_tab; jt++)
+      jt->table->null_row= 0;
+  }
+  else
+    join_tab->table->null_row=0;
+
   if (end_of_records)
   {
     enum_nested_loop_state nls=