Merge ibabaev@bk-internal.mysql.com:/home/bk/mysql-5.0

into rurik.mysql.com:/home/igor/mysql-5.0

mysql-test/r/select.result

@@ -2401,3 +2401,25 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
 1	SIMPLE	t2	ref	a	a	23	test.t1.a	2	
 DROP TABLE t1, t2;
+CREATE TABLE t1 ( city char(30) );
+INSERT INTO t1 VALUES ('London');
+INSERT INTO t1 VALUES ('Paris');
+SELECT * FROM t1 WHERE city='London';
+city
+London
+SELECT * FROM t1 WHERE city='london';
+city
+London
+EXPLAIN SELECT * FROM t1 WHERE city='London' AND city='london';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+SELECT * FROM t1 WHERE city='London' AND city='london';
+city
+London
+EXPLAIN SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
+SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+city
+London
+DROP TABLE t1;

mysql-test/t/select.test

@@ -1985,3 +1985,22 @@ EXPLAIN SELECT * FROM t1 LEFT JOIN t2 USE INDEX (a) ON t1.a=t2.a;
 EXPLAIN SELECT * FROM t1 LEFT JOIN t2 FORCE INDEX (a) ON t1.a=t2.a;
 
 DROP TABLE t1, t2;
+
+
+#
+# Test case for bug 7098: substitution of a constant for a string field 
+#
+
+CREATE TABLE t1 ( city char(30) );
+INSERT INTO t1 VALUES ('London');
+INSERT INTO t1 VALUES ('Paris');
+
+SELECT * FROM t1 WHERE city='London';
+SELECT * FROM t1 WHERE city='london';
+EXPLAIN SELECT * FROM t1 WHERE city='London' AND city='london';
+SELECT * FROM t1 WHERE city='London' AND city='london';
+EXPLAIN SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+SELECT * FROM t1 WHERE city LIKE '%london%' AND city='London';
+
+DROP TABLE t1;
+

sql/item.h

@@ -985,7 +985,7 @@ class Item_string :public Item
   Item *new_item() 
   {
     return new Item_string(name, str_value.ptr(), 
-    			   str_value.length(), &my_charset_bin);
+    			   str_value.length(), collation.collation);
   }
   Item *safe_charset_converter(CHARSET_INFO *tocs);
   String *const_string() { return &str_value; }