Hy ... i'm try开发者_高级运维ing to group_concat the primary key (id
) like this : SELECT GROUP_CONCAT (id) AS idz FROM table_name GROUP BY group;
but the result is [BLOB - 5 Bytes]
instead of 12,13,16,22
.
Why ?
Thank you
Try
SELECT group_concat(cast(id as char) SEPARATOR ',') as idz
FROM table_name
GROUP BY `group`
Have a look here.
according to the group by documentation The return value is a nonbinary or binary string, depending on whether the arguments are nonbinary or binary strings. The result type is TEXT or BLOB
http://dev.mysql.com/doc/refman/5.0/en/blob.html
It may be that you're result is best represented as a BLOB.
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