Merge

mysql-test/r/join_nested.result

@@ -1743,4 +1743,62 @@ ON t4.carrier = t1.carrier;
 COUNT(*)
 6
 DROP TABLE t1,t2,t3,t4,t5;
+CREATE TABLE t1 (
+pk int NOT NULL AUTO_INCREMENT PRIMARY KEY,
+a int DEFAULT NULL,
+KEY idx(a)
+);
+CREATE TABLE t2 (
+pk int  NOT NULL AUTO_INCREMENT PRIMARY KEY,
+a int DEFAULT NULL,
+KEY idx(a)
+);
+CREATE TABLE t3 (
+pk int NOT NULL AUTO_INCREMENT PRIMARY KEY,
+a int DEFAULT NULL,
+KEY idx(a)
+);
+INSERT INTO t1 VALUES 
+(1,2), (2,7), (3,5), (4,7), (5,5), (6,NULL), (7,NULL), (8,9);
+INSERT INTO t2 VALUES 
+(1,NULL), (4,2), (5,2), (3,4), (2,8);
+INSERT INTO t3 VALUES
+(1,9), (2,2), (3,5), (4,2), (5,7), (6,0), (7,5);
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a;
+pk	a	pk	a	pk	a
+1	2	4	2	2	2
+1	2	4	2	4	2
+1	2	5	2	2	2
+1	2	5	2	4	2
+2	7	NULL	NULL	NULL	NULL
+3	5	NULL	NULL	NULL	NULL
+4	7	NULL	NULL	NULL	NULL
+5	5	NULL	NULL	NULL	NULL
+6	NULL	NULL	NULL	NULL	NULL
+7	NULL	NULL	NULL	NULL	NULL
+8	9	NULL	NULL	NULL	NULL
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a
+WHERE t2.pk IS NULL;
+pk	a	pk	a	pk	a
+2	7	NULL	NULL	NULL	NULL
+3	5	NULL	NULL	NULL	NULL
+4	7	NULL	NULL	NULL	NULL
+5	5	NULL	NULL	NULL	NULL
+6	NULL	NULL	NULL	NULL	NULL
+7	NULL	NULL	NULL	NULL	NULL
+8	9	NULL	NULL	NULL	NULL
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a
+WHERE t3.pk IS NULL;
+pk	a	pk	a	pk	a
+2	7	NULL	NULL	NULL	NULL
+3	5	NULL	NULL	NULL	NULL
+4	7	NULL	NULL	NULL	NULL
+5	5	NULL	NULL	NULL	NULL
+6	NULL	NULL	NULL	NULL	NULL
+7	NULL	NULL	NULL	NULL	NULL
+8	9	NULL	NULL	NULL	NULL
+DROP TABLE t1, t2, t3;
 End of 5.0 tests

mysql-test/t/join_nested.test

@@ -1196,5 +1196,45 @@ SELECT COUNT(*)
 
 DROP TABLE t1,t2,t3,t4,t5;
 
+#
+# BUG#49322: Nested left joins + not-exist optimization
+#
+
+CREATE TABLE t1 (
+  pk int NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  a int DEFAULT NULL,
+  KEY idx(a)
+);
+CREATE TABLE t2 (
+  pk int  NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  a int DEFAULT NULL,
+  KEY idx(a)
+);
+CREATE TABLE t3 (
+  pk int NOT NULL AUTO_INCREMENT PRIMARY KEY,
+  a int DEFAULT NULL,
+  KEY idx(a)
+);
+
+INSERT INTO t1 VALUES 
+  (1,2), (2,7), (3,5), (4,7), (5,5), (6,NULL), (7,NULL), (8,9);
+INSERT INTO t2 VALUES 
+  (1,NULL), (4,2), (5,2), (3,4), (2,8);
+INSERT INTO t3 VALUES
+  (1,9), (2,2), (3,5), (4,2), (5,7), (6,0), (7,5);
+
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+  FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a;
+
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+  FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a
+  WHERE t2.pk IS NULL;
+
+SELECT t1.pk, t1.a, t2.pk, t2.a,t3.pk, t3.a 
+  FROM t1 LEFT JOIN (t2 LEFT JOIN t3 ON t3.a=t2.a) ON t2.a=t1.a
+  WHERE t3.pk IS NULL;
+
+DROP TABLE t1, t2, t3;
+
 --echo End of 5.0 tests
 

sql/sql_select.cc

@@ -11738,6 +11738,7 @@ evaluate_join_record(JOIN *join, JOIN_TAB *join_tab,
       condition is true => a match is found.
     */
     bool found= 1;
+    bool use_not_exists_opt= 0;
     while (join_tab->first_unmatched && found)
     {
       /*
@@ -11754,7 +11755,7 @@ evaluate_join_record(JOIN *join, JOIN_TAB *join_tab,
       for (JOIN_TAB *tab= first_unmatched; tab <= join_tab; tab++)
       {
         if (tab->table->reginfo.not_exists_optimize)
-          return NESTED_LOOP_NO_MORE_ROWS;
+          use_not_exists_opt= 1;
         /* Check all predicates that has just been activated. */
         /*
           Actually all predicates non-guarded by first_unmatched->found
@@ -11787,6 +11788,9 @@ evaluate_join_record(JOIN *join, JOIN_TAB *join_tab,
       join_tab->first_unmatched= first_unmatched;
     }
 
+    if (use_not_exists_opt)
+      return NESTED_LOOP_NO_MORE_ROWS;
+
     /*
       It was not just a return to lower loop level when one
       of the newly activated predicates is evaluated as false