Fixed bug mdev-4274.

This bug was the result of incompleteness of the patch for bug mdev-4177.
When an OR condition is simplified to a single conjunct it is merged
into the embedding AND condition. Multiple equalities are also merged,
and any field item involved in those equality should acquire a pointer
to a the multiple equality formed by this merge.

mysql-test/r/select.result

@@ -5049,6 +5049,7 @@ SELECT 1 FROM t1 GROUP BY 1;
 1
 1
 drop table t1;
+set sql_buffer_result= 0;
 End of 5.1 tests
 #
 # BUG#776274: substitution of a single row table
@@ -5132,4 +5133,38 @@ AND Time_zone_id = Time_zone_id
 OR Time_zone_id <> Time_zone_id ) 
 AND Use_leap_seconds <> 'N';
 Time_zone_id	Use_leap_seconds
+#
+# Bug mdev-4274: result of simplification of OR badly merged
+#                into embedding AND  
+#
+CREATE TABLE t1 (a int, b int, INDEX idx(b)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (8,8);
+CREATE TABLE t2 (c int, INDEX idx(c)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (8), (9);
+EXPLAIN EXTENDED
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	idx	NULL	NULL	NULL	1	100.00	
+1	SIMPLE	t2	ref	idx	idx	5	const	1	100.00	Using index
+Warnings:
+Note	1003	select 8 AS `a`,8 AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`c` = 8) and (8 < 33))
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+a	b	c
+8	8	8
+DROP TABLE t1,t2;
+#
+# Bug mdev-4413: another manifestations of bug mdev-2474
+#                (valgrind complains)
+#
+CREATE TABLE t1 (a int, b int) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (7,1);
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (0), (8);
+SELECT * FROM t1, t2 
+WHERE c = a AND
+( 0 OR ( b BETWEEN 45 AND 300 OR a > 45 AND a < 100 ) AND b = c );
+a	b	c
+DROP TABLE t1, t2;
 End of 5.3 tests

mysql-test/r/select_jcl6.result

@@ -5060,6 +5060,7 @@ SELECT 1 FROM t1 GROUP BY 1;
 1
 1
 drop table t1;
+set sql_buffer_result= 0;
 End of 5.1 tests
 #
 # BUG#776274: substitution of a single row table
@@ -5143,6 +5144,40 @@ AND Time_zone_id = Time_zone_id
 OR Time_zone_id <> Time_zone_id ) 
 AND Use_leap_seconds <> 'N';
 Time_zone_id	Use_leap_seconds
+#
+# Bug mdev-4274: result of simplification of OR badly merged
+#                into embedding AND  
+#
+CREATE TABLE t1 (a int, b int, INDEX idx(b)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (8,8);
+CREATE TABLE t2 (c int, INDEX idx(c)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (8), (9);
+EXPLAIN EXTENDED
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	idx	NULL	NULL	NULL	1	100.00	
+1	SIMPLE	t2	ref	idx	idx	5	const	1	100.00	Using index
+Warnings:
+Note	1003	select 8 AS `a`,8 AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`c` = 8) and (8 < 33))
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+a	b	c
+8	8	8
+DROP TABLE t1,t2;
+#
+# Bug mdev-4413: another manifestations of bug mdev-2474
+#                (valgrind complains)
+#
+CREATE TABLE t1 (a int, b int) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (7,1);
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (0), (8);
+SELECT * FROM t1, t2 
+WHERE c = a AND
+( 0 OR ( b BETWEEN 45 AND 300 OR a > 45 AND a < 100 ) AND b = c );
+a	b	c
+DROP TABLE t1, t2;
 End of 5.3 tests
 set join_cache_level=default;
 show variables like 'join_cache_level';

mysql-test/r/select_pkeycache.result

@@ -5049,6 +5049,7 @@ SELECT 1 FROM t1 GROUP BY 1;
 1
 1
 drop table t1;
+set sql_buffer_result= 0;
 End of 5.1 tests
 #
 # BUG#776274: substitution of a single row table
@@ -5132,4 +5133,38 @@ AND Time_zone_id = Time_zone_id
 OR Time_zone_id <> Time_zone_id ) 
 AND Use_leap_seconds <> 'N';
 Time_zone_id	Use_leap_seconds
+#
+# Bug mdev-4274: result of simplification of OR badly merged
+#                into embedding AND  
+#
+CREATE TABLE t1 (a int, b int, INDEX idx(b)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (8,8);
+CREATE TABLE t2 (c int, INDEX idx(c)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (8), (9);
+EXPLAIN EXTENDED
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
+1	SIMPLE	t1	system	idx	NULL	NULL	NULL	1	100.00	
+1	SIMPLE	t2	ref	idx	idx	5	const	1	100.00	Using index
+Warnings:
+Note	1003	select 8 AS `a`,8 AS `b`,`test`.`t2`.`c` AS `c` from `test`.`t1` join `test`.`t2` where ((`test`.`t2`.`c` = 8) and (8 < 33))
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+WHERE 1 IS NULL OR b < 33 AND b = c;
+a	b	c
+8	8	8
+DROP TABLE t1,t2;
+#
+# Bug mdev-4413: another manifestations of bug mdev-2474
+#                (valgrind complains)
+#
+CREATE TABLE t1 (a int, b int) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (7,1);
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (0), (8);
+SELECT * FROM t1, t2 
+WHERE c = a AND
+( 0 OR ( b BETWEEN 45 AND 300 OR a > 45 AND a < 100 ) AND b = c );
+a	b	c
+DROP TABLE t1, t2;
 End of 5.3 tests

mysql-test/r/subselect_sj2_mat.result

@@ -1380,7 +1380,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 2	MATERIALIZED	t2	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 2	MATERIALIZED	t3	hash_ALL	NULL	#hash#$hj	5	test.t2.i2	3	100.00	Using where; Using join buffer (flat, BNLH join)
 Warnings:
-Note	1003	select `test`.`t1`.`i1` AS `i1` from `test`.`t1` semi join (`test`.`t2` join `test`.`t3`) where ((`test`.`t3`.`i3` = `test`.`t2`.`i2`) and (`test`.`t1`.`i1` = `test`.`t2`.`i2`) and (`test`.`t3`.`i3` > 0))
+Note	1003	select `test`.`t1`.`i1` AS `i1` from `test`.`t1` semi join (`test`.`t2` join `test`.`t3`) where ((`test`.`t3`.`i3` = `test`.`t2`.`i2`) and (`test`.`t1`.`i1` = `test`.`t2`.`i2`) and (`test`.`t2`.`i2` > 0))
 SELECT * FROM t1 
 WHERE i1 IN (SELECT i3 FROM t2, t3 WHERE i3 > 0 AND i3 = i2 OR 1=2);
 i1

mysql-test/t/select.test

@@ -4241,6 +4241,7 @@ SELECT f1 FROM t1 GROUP BY 1;
 SELECT f1 FROM t1 GROUP BY '123' = 'abc';
 SELECT 1 FROM t1 GROUP BY 1;
 drop table t1;
+set sql_buffer_result= 0;
 
 --echo End of 5.1 tests
 
@@ -4305,4 +4306,40 @@ WHERE ( NOT (Use_leap_seconds <= Use_leap_seconds AND Time_zone_id != 1)
      OR Time_zone_id <> Time_zone_id ) 
   AND Use_leap_seconds <> 'N';
 
+--echo #
+--echo # Bug mdev-4274: result of simplification of OR badly merged
+--echo #                into embedding AND  
+--echo #
+
+CREATE TABLE t1 (a int, b int, INDEX idx(b)) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (8,8);
+
+CREATE TABLE t2 (c int, INDEX idx(c)) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (8), (9);
+
+EXPLAIN EXTENDED
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+  WHERE 1 IS NULL OR b < 33 AND b = c;
+SELECT * FROM t1 INNER JOIN t2 ON ( c = a ) 
+  WHERE 1 IS NULL OR b < 33 AND b = c;
+
+DROP TABLE t1,t2;
+
+--echo #
+--echo # Bug mdev-4413: another manifestations of bug mdev-2474
+--echo #                (valgrind complains)
+--echo #
+
+CREATE TABLE t1 (a int, b int) ENGINE=MyISAM;
+INSERT INTO t1 VALUES (7,1);
+
+CREATE TABLE t2 (c int) ENGINE=MyISAM;
+INSERT INTO t2 VALUES (0), (8);
+
+SELECT * FROM t1, t2 
+  WHERE c = a AND
+        ( 0 OR ( b BETWEEN 45 AND 300 OR a > 45 AND a < 100 ) AND b = c );
+
+DROP TABLE t1, t2;
+
 --echo End of 5.3 tests

sql/sql_select.cc

@@ -13195,7 +13195,24 @@ remove_eq_conds(THD *thd, COND *cond, Item::cond_result *cond_value)
             if (new_item_and_list->is_empty())
               li.remove();
             else
-              li.replace(*new_item_and_list);
+	    {
+              Item *list_item;
+              Item *new_list_item;      
+              List_iterator<Item> it(*new_item_and_list);
+              while ((list_item= it++))
+	      {
+                uchar* is_subst_valid= (uchar *) Item::ANY_SUBST;
+                new_list_item= 
+                  list_item->compile(&Item::subst_argument_checker,
+                                         &is_subst_valid, 
+                                         &Item::equal_fields_propagator,
+                                         (uchar *) &cond_and->cond_equal);
+                if (new_list_item != list_item)
+                  it.replace(new_list_item);
+                new_list_item->update_used_tables();
+              }              
+              li.replace(*new_item_and_list);  
+            }
             cond_and_list->concat((List<Item>*) cond_equal_items); 
           }
           else if (new_item->type() == Item::FUNC_ITEM &&