Fixed LP bugs BUG#729067/730466.

Do not reset the value of the item_equal field in the Item_field object
once it has been set.

mysql-test/r/join.result

@@ -1285,3 +1285,38 @@ a	b	a	a	b
 1	1	1	1	1
 1	1	1	1	1
 drop table t1,t2,t3;
+#
+# BUG#729067/730466: unexpected 'Range checked for each record'
+#                    for queries with OR in WHERE clause 
+#
+CREATE TABLE t1 (f1 int, f2 int) ;
+INSERT INTO t1 VALUES (4,0),(5,1);
+CREATE TABLE t2 (f1 int, f2 int, KEY (f2)) ;
+INSERT INTO t2 VALUES (5,7), (8,9);
+EXPLAIN
+SELECT * FROM t1 STRAIGHT_JOIN t2 ON t2.f1 = t1.f1
+WHERE t1.f1<>0 OR t1.f2<>0 AND t1.f1 = t2.f2;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	SIMPLE	t2	ALL	f2	NULL	NULL	NULL	2	Using where; Using join buffer (flat, BNL join)
+SELECT * FROM t1 STRAIGHT_JOIN t2 ON t2.f1 = t1.f1
+WHERE t1.f1<>0 OR t1.f2<>0 AND t1.f1 = t2.f2;
+f1	f2	f1	f2
+5	1	5	7
+DROP TABLE t1,t2;
+CREATE TABLE t1(f1 int PRIMARY KEY, f2 int) ;
+INSERT INTO t1 VALUES (9,4), (10,9);
+CREATE TABLE t2(f1 int PRIMARY KEY, f2 int) ;
+INSERT INTO t2 VALUES (9,4), (10,9);
+EXPLAIN
+SELECT STRAIGHT_JOIN * FROM t1 JOIN t2 ON t2.f2 = t1.f1
+WHERE t1.f1 IN (SELECT f1 FROM t1) AND t1.f1 = t2.f1 OR t1.f1 = 9;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	2	Using where
+1	PRIMARY	t2	ALL	PRIMARY	NULL	NULL	NULL	2	Using where; Using join buffer (flat, BNL join)
+2	SUBQUERY	t1	index	NULL	PRIMARY	4	NULL	2	Using index
+SELECT STRAIGHT_JOIN * FROM t1 JOIN t2 ON t2.f2 = t1.f1
+WHERE t1.f1 IN (SELECT f1 FROM t1) AND t1.f1 = t2.f1 OR t1.f1 = 9;
+f1	f2	f1	f2
+9	4	10	9
+DROP TABLE t1,t2;

mysql-test/t/join.test

@@ -964,3 +964,36 @@ where t2.a=1 and t2.b=t1.a and t1.a=t3.b and t3.a=1;
 
 drop table t1,t2,t3;
 
+--echo #
+--echo # BUG#729067/730466: unexpected 'Range checked for each record'
+--echo #                    for queries with OR in WHERE clause 
+--echo #
+
+CREATE TABLE t1 (f1 int, f2 int) ;
+INSERT INTO t1 VALUES (4,0),(5,1);
+
+CREATE TABLE t2 (f1 int, f2 int, KEY (f2)) ;
+INSERT INTO t2 VALUES (5,7), (8,9);
+
+EXPLAIN
+SELECT * FROM t1 STRAIGHT_JOIN t2 ON t2.f1 = t1.f1
+  WHERE t1.f1<>0 OR t1.f2<>0 AND t1.f1 = t2.f2;
+SELECT * FROM t1 STRAIGHT_JOIN t2 ON t2.f1 = t1.f1
+  WHERE t1.f1<>0 OR t1.f2<>0 AND t1.f1 = t2.f2;
+
+DROP TABLE t1,t2;
+
+CREATE TABLE t1(f1 int PRIMARY KEY, f2 int) ;
+INSERT INTO t1 VALUES (9,4), (10,9);
+
+CREATE TABLE t2(f1 int PRIMARY KEY, f2 int) ;
+INSERT INTO t2 VALUES (9,4), (10,9);
+
+EXPLAIN
+SELECT STRAIGHT_JOIN * FROM t1 JOIN t2 ON t2.f2 = t1.f1
+  WHERE t1.f1 IN (SELECT f1 FROM t1) AND t1.f1 = t2.f1 OR t1.f1 = 9;
+SELECT STRAIGHT_JOIN * FROM t1 JOIN t2 ON t2.f2 = t1.f1
+  WHERE t1.f1 IN (SELECT f1 FROM t1) AND t1.f1 = t2.f1 OR t1.f1 = 9;
+
+DROP TABLE t1,t2;
+

sql/item_cmpfunc.cc

@@ -5723,7 +5723,8 @@ bool Item_equal::fix_fields(THD *thd, Item **ref)
     not_null_tables_cache|= tmp_table_map;
     if (item->maybe_null)
       maybe_null=1;
-    item->item_equal= this;
+    if (!item->item_equal)
+      item->item_equal= this;
   }
   fix_length_and_dec();
   fixed= 1;