[Rt-devel] Slowest query in our setup

Joop van de Wege JoopvandeWege at mococo.nl
Sun Aug 1 16:11:47 EDT 2004

Hi All,

I verified that query against our Oracle9i RT3 instance and I get rather
decent performance. The problem I see is that a full table scan is done
over table GROUPS. This is cause by the fact that the index on DOMAIN
isn't used. If I add a level one index, just using DOMAIN as an indexed
column performance goes up 3 times and explain plan shows the use of the
I have seen this more often that apps use multiple key indices but that
often doesn't work, atleast not with Oracle.

On a side note:
Maybe not everyone knows this but if you use mod_perl and RT(2/3) then
you can use this in httpd.conf:
PerlSetEnv DBI_PROFILE DBI::ProfileDumper::Apache  
At each stop/start of Apache you'll get profiling data in your logs
directory which you can analyse with dbiprof. If a mod_perl/apache
process terminaties due to max accesses reached it will also dump its
profile data.
This way one can find quite a few interesting things.


Joop van de Wege <JoopvandeWege at mococo.nl>

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