i've got a strange problem with concat() function
i have the following data structure:
CREATE TABLE table1 (
field1 int(11) NOT NULL auto_increment,
PRIMARY KEY (field1)
) ENGINE=MyISAM DEFAULT CHARSET=cp1251 AUTO_INCREMENT=3;
CREATE TABLE table2 (
field2 varchar(255) NOT NULL default ''
) ENGINE=InnoDB DEFAULT CHARSET=cp1251;
INSERT INTO table1 VALUES (1);
INSERT INTO table1 VALUES (2);
INSERT INTO table2 VALUES ('test');
When i try to execute the following query
(the query is meaningless -- it is generated just for debug purpose.
the original query where the problem occured is too long and
complicated)
SELECT
COUNT(DISTINCT field1) as value1,
CONCAT(field2, '-') as value2
FROM
table1,
table2
GROUP
BY value2
i get this error:
ERROR 2006 (HY000): MySQL server has gone away
No connection. Trying to reconnect...
Connection id: 6
Current database: test
ERROR 2013 (HY000): Lost connection to MySQL server during query
but if i change my query to this one everything is fine
SELECT
COUNT(DISTINCT field1) as value1,
CONCAT(field2, '') as value2
FROM
table1,
table2
GROUP
BY value2
(here CONCAT(field2, '-') is replaced with CONCAT(field2, '') )
does anyone know what the matter is?
ps
my mysql version is
mysql Ver 14.7 Distrib 4.1.12, for unknown-freebsd4.6 (i386) using EditLine wrapper
and my system is FreeBSD 4.6
--
Best regards,
Sergey Averyanov
mailto:averyanov@stripped
