Commit 4b2c3ac4 authored by unknown's avatar unknown
Browse files

Merge gkodinov@bk-internal.mysql.com:/home/bk/mysql-5.1-opt 

into  rakia.gmz:/home/kgeorge/mysql/autopush/B16590-5.1-opt


mysql-test/r/order_by.result:
  Auto merged
mysql-test/t/order_by.test:
  Auto merged
sql/sql_select.cc:
  Auto merged
parents 9af4bbc7 2c6e678d

mysql-test/r/order_by.result

+9 −0
Original line number Diff line number Diff line
@@ -926,3 +926,12 @@ NULL 
2

3

DROP TABLE t1,t2,t3,t4;

CREATE TABLE t1 (a INT, b INT, PRIMARY KEY (a), UNIQUE KEY b (b));

INSERT INTO t1 VALUES (1,1),(2,2);

CREATE TABLE t2 (a INT, b INT, KEY a (a,b));

INSERT INTO t2 VALUES (1,1),(1,2),(2,1),(2,2);

EXPLAIN SELECT 1 FROM t1,t2 WHERE t1.b=2 AND t1.a=t2.a ORDER BY t2.b;

id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	const	PRIMARY,b	b	5	const	1	

1	SIMPLE	t2	ref	a	a	5	const	2	Using where; Using index

DROP TABLE t1,t2;

mysql-test/t/order_by.test

+13 −0
Original line number Diff line number Diff line
@@ -640,3 +640,16 @@ SELECT t2.b FROM t1 LEFT JOIN (t2, t3 LEFT JOIN t4 ON t3.a=t4.a) 
ON (t1.a=t2.a AND t1.b=t3.b) order by t2.b;



DROP TABLE t1,t2,t3,t4;



#

# BUG#16590: Optimized does not do right "const" table pre-read

#

CREATE TABLE t1 (a INT, b INT, PRIMARY KEY (a), UNIQUE KEY b (b));

INSERT INTO t1 VALUES (1,1),(2,2);



CREATE TABLE t2 (a INT, b INT, KEY a (a,b));

INSERT INTO t2 VALUES (1,1),(1,2),(2,1),(2,2);



EXPLAIN SELECT 1 FROM t1,t2 WHERE t1.b=2 AND t1.a=t2.a ORDER BY t2.b;



DROP TABLE t1,t2;

sql/sql_select.cc

+16 −0
Original line number Diff line number Diff line
@@ -7722,6 +7722,22 @@ static void update_const_equal_items(COND *cond, JOIN_TAB *tab) 
        key_map possible_keys= field->key_start;

        possible_keys.intersect(field->table->keys_in_use_for_query);

        stat[0].const_keys.merge(possible_keys);



        /*

          For each field in the multiple equality (for which we know that it 

          is a constant) we have to find its corresponding key part, and set 

          that key part in const_key_parts.

        */  

        if (!possible_keys.is_clear_all())

        {

          TABLE *tab= field->table;

          KEYUSE *use;

          for (use= stat->keyuse; use && use->table == tab; use++)

            if (possible_keys.is_set(use->key) && 

                tab->key_info[use->key].key_part[use->keypart].field ==

                field)

              tab->const_key_parts[use->key]|= use->keypart_map;

        }

      }

    }

  }