How do we want CC list or commenter "does not match" to work??

Joel Peshkin bugreport at
Sat Feb 7 16:03:16 UTC 2004

Bradley Baetz wrote:

> <snip>
>Now, theres a problem with the above. That assumes that we know the 
>userid of the person we're looking for. Lets assume that we don't:
>bbaetz=> explain analyze select bug_id from bugs where bug_id not in
>(select bug_id from cc where who = (SELECT userid FROM profiles where 
>Time: 261.747 ms
>The best I can come up with without subselects is:
>bbaetz=> explain analyze select bugs.bug_id from bugs left join cc on 
>bugs.bug_id=cc.bug_id left join profiles on cc.who = profiles.userid and 
>profiles.login_name='QJEYECRS' group by bugs.bug_id having 
>count(login_name) = 0;
>Time: 30372.595 ms
>which swaps heavily. I don't think that that can be reliably extended to 
>include other constraints.

It may not be quite that bad. already uses distinct and 
avoids joining the profiles when it can by querying the profiles first 
and returning either a userid or a list of userids.  That could make a 
substantial difference. 

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