MDEV-5369: Wrong result (0 instead of NULL) on 2nd execution of PS with LEFT JOIN, TEMPTABLE view

Set of JOIN_TYPE_OUTER made only once to avoid interference with optimization joins which made only once per query.

mysql-test/r/ps.result

@@ -3307,4 +3307,25 @@ c1
 NULL
 2
 DROP TABLE t1,t2;
+#
+# MDEV-5369: Wrong result (0 instead of NULL) on 2nd execution of 
+# PS with LEFT JOIN, TEMPTABLE view
+#
+CREATE TABLE t1 (a INT) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (0),(8);
+CREATE TABLE t2 (pk INT PRIMARY KEY) ENGINE=MyISAM;
+CREATE ALGORITHM=TEMPTABLE VIEW v2 AS SELECT * FROM t2;
+SELECT SUM(pk) FROM t1 LEFT JOIN v2 ON a = pk;
+SUM(pk)
+NULL
+PREPARE stmt FROM "SELECT SUM(pk) FROM t1 LEFT JOIN v2 ON a = pk";
+EXECUTE stmt;
+SUM(pk)
+NULL
+EXECUTE stmt;
+SUM(pk)
+NULL
+DEALLOCATE PREPARE stmt;
+DROP VIEW v2;
+DROP TABLE t1, t2;
 # End of 5.3 tests

mysql-test/t/ps.test

@@ -3330,4 +3330,27 @@ EXECUTE stmt;
 
 DROP TABLE t1,t2;
  
+
+--echo #
+--echo # MDEV-5369: Wrong result (0 instead of NULL) on 2nd execution of 
+--echo # PS with LEFT JOIN, TEMPTABLE view
+--echo #
+
+
+CREATE TABLE t1 (a INT) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (0),(8);
+
+CREATE TABLE t2 (pk INT PRIMARY KEY) ENGINE=MyISAM;
+CREATE ALGORITHM=TEMPTABLE VIEW v2 AS SELECT * FROM t2;
+
+SELECT SUM(pk) FROM t1 LEFT JOIN v2 ON a = pk;
+
+PREPARE stmt FROM "SELECT SUM(pk) FROM t1 LEFT JOIN v2 ON a = pk";
+EXECUTE stmt; 
+EXECUTE stmt;
+DEALLOCATE PREPARE stmt;
+
+DROP VIEW v2;
+DROP TABLE t1, t2;
+
 --echo # End of 5.3 tests

sql/sql_derived.cc

@@ -627,7 +627,7 @@ bool mysql_derived_prepare(THD *thd, LEX *lex, TABLE_LIST *derived)
     if ((res= sl->handle_derived(lex, DT_PREPARE)))
       goto exit;
 
-    if (derived->outer_join)
+    if (derived->outer_join && sl->first_cond_optimization)
     {
       /* Mark that table is part of OUTER JOIN and fields may be NULL */
       for (TABLE_LIST *cursor= (TABLE_LIST*) sl->table_list.first;