Posted by Toby A Inkster on 07/27/07 09:46
gosha bine wrote:
> Don't know about "most" ones, mysql docs explicitly says they're equivalent
> http://dev.mysql.com/doc/refman/5.0/en/distinct-optimization.html
It says that SELECT DISTINCT and GROUP BY *usually* end up generating the
same execution plan, so there won't be a performance difference.
--
Toby A Inkster BSc (Hons) ARCS
[Geek of HTML/SQL/Perl/PHP/Python/Apache/Linux]
[OS: Linux 2.6.12-12mdksmp, up 36 days, 13:07.]
Cryptography Challenge
http://tobyinkster.co.uk/blog/2007/07/24/crypto-challenge/
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