maria-developers team mailing list archive

[Alexander Barkov <bar@xxxxxxxxxxx>]

Hi Hartmut,


On 01/10/2015 04:08 AM, Hartmut Holzgraefe wrote:
> Any idea how that happened, as I can't find anything that seems
> to be related in the 5.5.38 changelog?
>
> http://bugs.mysql.com/bug.php?id=68557

From a glance, the patch for

"MDEV-5459 Illegal mix of collations for datetime'

fixed this problem as well (see the patch below).


Before this patch it erroneously added a character set converter
and compared as strings:


DROP TABLE IF EXISTS t1;
CREATE TABLE t1 (d DATE); INSERT INTO t1 VALUES('2013-02-28');
SET NAMES sjis;
EXPLAIN EXTENDED SELECT * FROM t1 WHERE d = '2013/02/28';
SHOW WARNINGS;

+-------+------+-----------------------------------------------------------------------------------------------------------+
| Level | Code | Message 
                                                   |
+-------+------+-----------------------------------------------------------------------------------------------------------+
| Note  | 1003 | select `test`.`t1`.`d` AS `d` from `test`.`t1` where 
(convert(`test`.`t1`.`d` using sjis) = '2013/02/28') |
+-------+------+-----------------------------------------------------------------------------------------------------------+


After this patch it does not add the converter and compares as dates.




> === modified file 'mysql-test/r/ctype_cp1251.result'
> --- mysql-test/r/ctype_cp1251.result	2014-04-28 11:56:31 +0000
> +++ mysql-test/r/ctype_cp1251.result	2014-04-28 13:01:58 +0000
> @@ -3282,5 +3282,15 @@ SELECT COALESCE(IF(test1=1, NULL, 1), te
>  COALESCE(IF(test1=1, NULL, 1), test2)
>  DROP TABLE t1;
>  #
> +# MDEV-5459 Illegal mix of collations for datetime
> +#
> +SET NAMES cp1251;
> +CREATE TABLE t1 (dt DATETIME);
> +INSERT INTO t1 VALUES ('2014-01-02 10:20:30');
> +SELECT date(dt) FROM t1 WHERE (CASE WHEN 1 THEN date(dt) ELSE null END >= '2013-12-01 00:00:00');
> +date(dt)
> +2014-01-02
> +DROP TABLE t1;
> +#
>  # End of 5.5 tests
>  #
>
> === modified file 'mysql-test/t/ctype_cp1251.test'
> --- mysql-test/t/ctype_cp1251.test	2011-10-19 19:45:18 +0000
> +++ mysql-test/t/ctype_cp1251.test	2014-04-28 13:01:58 +0000
> @@ -95,6 +95,14 @@ SELECT COALESCE(IF(test1=1, 1, NULL), te
>  SELECT COALESCE(IF(test1=1, NULL, 1), test2) FROM t1;
>  DROP TABLE t1;
>
> +--echo #
> +--echo # MDEV-5459 Illegal mix of collations for datetime
> +--echo #
> +SET NAMES cp1251;
> +CREATE TABLE t1 (dt DATETIME);
> +INSERT INTO t1 VALUES ('2014-01-02 10:20:30');
> +SELECT date(dt) FROM t1 WHERE (CASE WHEN 1 THEN date(dt) ELSE null END >= '2013-12-01 00:00:00');
> +DROP TABLE t1;
>
>  --echo #
>  --echo # End of 5.5 tests
>
> === modified file 'sql/item_cmpfunc.cc'
> --- sql/item_cmpfunc.cc	2014-04-28 11:56:31 +0000
> +++ sql/item_cmpfunc.cc	2014-04-28 13:01:58 +0000
> @@ -549,8 +549,8 @@ void Item_bool_func2::fix_length_and_dec
>    */
>
>    DTCollation coll;
> -  if (args[0]->result_type() == STRING_RESULT &&
> -      args[1]->result_type() == STRING_RESULT &&
> +  if (args[0]->cmp_type() == STRING_RESULT &&
> +      args[1]->cmp_type() == STRING_RESULT &&
>        agg_arg_charsets_for_comparison(coll, args, 2))
>      return;