[wp-trac] Re: [WordPress Trac] #9559: Site search results can include passworded posts

[WordPress Trac]

#9559: Site search results can include passworded posts
--------------------------+-------------------------------------------------
 Reporter:  coffee2code   |       Owner:  ShaneF   
     Type:  defect (bug)  |      Status:  assigned 
 Priority:  normal        |   Milestone:  2.8      
Component:  General       |     Version:  2.7.1    
 Severity:  normal        |    Keywords:  has-patch
--------------------------+-------------------------------------------------

Comment(by Denis-de-Bernardy):

 Replying to [comment:3 ryan]:
 > There's no index on post_password, so this will likely seriously degrade
 query performance.

 No so. Or rather, only if there are multitudes of posts that have a
 password. Else, it'll just filter out a result here and there.

 Also note that, if the vast majority of posts happen to have no passwords,
 and you look for posts without one as the only criteria in your query, the
 optimizer will simply ignore that index: A seq scan, on which you filter
 out those that have a faster, will generally be faster.

 In fact, the likelihood is that you can even toss the following in,
 without any noticeable degradation of speed:

 {{{
 AND ( post_password = '' OR post_author = $user_id )
 }}}

 The optimizer would then filter the results returned by the index used
 based on that criteria, like this:

 {{{
 nested loop on index
   for each row
     check the above
     break at $limit rows
 }}}

-- 
Ticket URL: <http://core.trac.wordpress.org/ticket/9559#comment:6>
WordPress Trac <http://trac.wordpress.org/>
WordPress blogging software