From: Rick James
Date: January 7 2013 6:46pm
Subject: RE: questions about group_concat_max_len
List-Archive: http://lists.mysql.com/mysql/228861
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I suspect, without knowing for sure, that the server will preallocate the 1=
6MB (or whatever) and then proceed to fill it in.  Such a malloc is not cos=
tly, and not risky (unless you have thousands of threads doing the same thi=
ng at the same time).

Who cares?  If GROUP_CONCAT() is what you need, then pay whatever the price=
 is.

"If you hit a MySQL limit, you are probably mis-using MySQL."

> -----Original Message-----
> From: Paul Halliday [mailto:paul.halliday@stripped]
> Sent: Friday, January 04, 2013 5:12 AM
> To: mysql mailing list
> Subject: questions about group_concat_max_len
>=20
> Are there performance considerations if this value is set really high,
> say big enough to fit into max_allowed_packet? Does it matter?
>=20
> Thanks.
>=20
> --
> Paul Halliday
> http://www.pintumbler.org/
>=20
> --
> MySQL General Mailing List
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