database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-29 05:21:33 +03:00
Code Activity

Fixed bug #32815.

Browse Source 
The index (key_part_1, key_part-2) was erroneously considered as compatible
with the required ordering in the function test_test_if_order_by_key when 
a query with an ORDER BY clause contained a condition of the form
  key_part_1=const OR key_part_1 IS NULL 
and the order list contained only key_part_2. This happened because the value
of the const_key_parts field in the KEYUSE structure was not formed correctly
for the keys that could be used for ref_or_null access. 
This was fixed in the code of the update_ref_and_keys function.
The problem could not manifest itself for MyISAM databases because the
implementation of the keys_to_use_for_scanning() handler function always
returns an empty bitmap for the MyISAM engine.


mysql-test/r/innodb_mysql.result:
  Added a test case for bug #32815.
mysql-test/t/innodb_mysql.test:
  Added a test case for bug #32815.
sql/sql_select.cc:
  Fixed bug #32815.
  The index (key_part_1, key_part-2) was erroneously considered as compatible
  with the required ordering in the function test_test_if_order_by_key when 
  a query with an ORDER BY clause contained a condition of the form
    key_part_1=const OR key_part_1 IS NULL 
  and the order list contained only key_part_2. This happened because the value
  of the const_key_parts field in the KEYUSE structure was not formed correctly
  for the keys that could be used for ref_or_null access. 
  This was fixed in the code of the update_ref_and_keys function.
This commit is contained in:
unknown
2007-12-07 17:14:59 -08:00
parent 6a72267d05
commit d776054e00
3 changed files with 28 additions and 1 deletions
Download Patch File Download Diff File Expand all files Collapse all files

12
mysql-test/r/innodb_mysql.result
View File

@ -1213,4 +1213,16 @@ a b
3 2
1 1
DROP TABLE t1;
CREATE TABLE t1 (id int, type char(6), d int, INDEX idx(id,d)) ENGINE=InnoDB;
INSERT INTO t1 VALUES
(191, 'member', 1), (NULL, 'member', 3), (NULL, 'member', 4), (201, 'member', 2);
EXPLAIN SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t1 ALL idx NULL NULL NULL 3 Using where; Using filesort
SELECT * FROM t1 WHERE id=191 OR id IS NULL ORDER BY d;
id type d
191 member 1
NULL member 3
NULL member 4
DROP TABLE t1;
End of 5.0 tests