Better way to do SELECT with GROUP BY

Posted by Luca Romagnoli on Stack Overflow See other posts from Stack Overflow or by Luca Romagnoli
Published on 2010-03-26T23:29:19Z Indexed on 2010/03/27 13:33 UTC
Read the original article Hit count: 266

Filed under:

sql

|

mysql

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Performance

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join

|

group-by

Hi i've wrote a query that works:

SELECT `comments`.* FROM `comments` 
RIGHT JOIN (SELECT MAX( id ) AS id, core_id, topic_id 
FROM comments GROUP BY core_id, topic_id order by id desc) comm 
ON comm.id = comments.id LIMIT 10

I want know if it is possible (and how) to rewrite it to get better performance.

Thanks

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