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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>In the process of investigating the performance of using
Shredder to delete tickets, I found an index that seems to have a considerable
improvement on performance, even above the indexes that are suggested in the
documentation. I simply added:<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>CREATE INDEX SHREDDER_CGM3 ON CachedGroupMembers(Val, Id);<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Before, when I had no indexes, deleting 500 tickets (there
are ~ 100,000 in our database), the process took about 2 hours and 30 minutes.
After adding the suggested indexes (which I found in the CPAN documentation),
the process took about 1 hour, 15 minutes. After adding the above index, the
process took about 16 minutes. I stumbled upon this while using the tool mytop
(available at <a href="http://jeremy.zawodny.com/mysql/mytop/">http://jeremy.zawodny.com/mysql/mytop/</a>).<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am pretty certain that, despite the occasionally
self-referrential nature of the Val field in the CGM table, this index shouldn’t
lead to any difference in results, ordering, or completeness in deletion. I
haven’t had the time to check, though – so obviously I take no
responsibility for any huge catastrophes that may occur on your particular
database.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Anyway, thanks to Ruslan Zakirov for a great tool.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Cheers,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>-Drew Day<o:p></o:p></span></font></p>
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