Commit afa8187f authored by evgen@moonbone.local's avatar evgen@moonbone.local
Browse files

Fix bug #13218: InnoDB: using a partial-field key prefix in search 

  
This is backport from 5.0 of fix for bug #11039
parent 15bf8f6a

mysql-test/r/innodb.result

+9 −0
Original line number Diff line number Diff line
@@ -1685,3 +1685,12 @@ explain select * from t1 order by a,b,c,d; 
id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra

1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	3	Using filesort

drop table t1;

create table t1 (a char(1), b char(1), key(a, b)) engine=innodb;

insert into t1 values ('8', '6'), ('4', '7');

select min(a) from t1;

min(a)

4

select min(b) from t1 where a='8';

min(b)

6

drop table t1;

mysql-test/t/innodb.test

+9 −0
Original line number Diff line number Diff line
@@ -1230,4 +1230,13 @@ select * from t1 order by a,b,c,d; 
explain select * from t1 order by a,b,c,d;

drop table t1;



#

# BUG#11039,#13218 Wrong key length in min()

#



create table t1 (a char(1), b char(1), key(a, b)) engine=innodb;

insert into t1 values ('8', '6'), ('4', '7');

select min(a) from t1;

select min(b) from t1 where a='8';

drop table t1;

# End of 4.1 tests

sql/opt_sum.cc

+2 −1
Original line number Diff line number Diff line
@@ -661,7 +661,8 @@ static bool find_key_for_maxmin(bool max_fl, TABLE_REF *ref, 
              If key_part2 may be NULL, then we want to find the first row

              that is not null

            */

            ref->key_buff[ref->key_length++]= 1;

            ref->key_buff[ref->key_length]= 1;

            ref->key_length+= part->store_length;

            *range_fl&= ~NO_MIN_RANGE;

            *range_fl|= NEAR_MIN;                // > NULL

          }