[wp-trac] Re: [WordPress Trac] #8561: query in meta_form() function in /wp-admin/includes/template.php causes post/page editing to load slowly

[WordPress Trac]

#8561: query in meta_form() function in /wp-admin/includes/template.php causes
post/page editing to load slowly
--------------------------+-------------------------------------------------
 Reporter:  fastpipe      |       Owner:  anonymous       
     Type:  defect (bug)  |      Status:  new             
 Priority:  high          |   Milestone:  2.8             
Component:  Optimization  |     Version:  2.7             
 Severity:  critical      |    Keywords:  has-patch tested
--------------------------+-------------------------------------------------
Changes (by vladimir_kolesnikov):

 * cc: vladimir@… (added)


Comment:

 Replying to [comment:7 Denis-de-Bernardy]:
 > patch is invalid. the group by is not the issue, and the distinct
 statement can only end up adding an extra sort operator to the full query,
 while doing the same as a group by.

 FYI: DISTINCT is the same as GROUP BY field ORDER BY NULL. Since the index
 is used for GROUP BY, no sort will take place (note the absense of Using
 filesort in EXPLAIN).

 Although I agree that your query is a bit better as it allows to avoid
 creating a temporary table.

-- 
Ticket URL: <http://core.trac.wordpress.org/ticket/8561#comment:9>
WordPress Trac <http://trac.wordpress.org/>
WordPress blogging software