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[listas at askterisk.com]

Hello all, This is my first message on the list, i´m pretty new to FS. I was playing a bit with mod_lcr and found that the sql query for fetching the lowest rate can be changed to a better use of indexes, at least on mysql. Anyone can do some test using other DBs? The change i've made was simple, the original query was something about "... AND digits IN (12345, 1234, 123, 12, 1) ..." and using EXPLAIN i saw that it was using carrier_id as key for the biggest table and not digits. I've changed the code so the query is " AND (digits='12345' OR digits='1234' OR digits='123' OR digits='12' OR digits='1') " and mysql uses the index from the digits row, reducing the returned resultset of the subquery from all the digits from a carrier to the number of "OR" in the query (in my case, from 19850+ to 14). Anyone think that this may be a nice change? or it is just a bad use of indexes by mysql? Regards, Marcelo Sosa

[rupa at rupa.com]

Hmm.... This is because mysql is "dumb" Anyway, if you wanted
quoted digits, there is an option to enable that in the mod_lcr config
file.

http://wiki.freeswitch.org/wiki/Mod_lcr#Advanced_Usage

Specifically, look at the parameter: quote_in_list

The most efficient way (that I know of) to use mod_lcr is to use
postgresql and the prefix postgres module which uses a custom datatype
and a GIST index for the prefix column.

On Thu, Sep 17, 2009 at 9:24 PM, Marcelo Sosa - LST
<listas@askterisk.com> wrote:

[listas at askterisk.com]

Hello,

I know that mysql is dumb, but i´m postgresql-fobic (i was happy using
pgsql, until i found a bug in the restore of backups, that makes the backup
unable to be restored, very bad day)
Anyway, I was refering to the change from "digits IN (a list of digits)" to
"(digits='xx' OR digits='xxx')", not the quote_in_list option that i found
when i was touching a bit of code.
For the list-archives then, mysql may prefer a different query format to
speed up lcr matches. I´ll test with postgres and check it has any
differences by using one method or another, if not may be we can change the
code so it uses the fastest way for mysql.

Regards,
Marcelo Sosa

----- Original Message -----
From: "Rupa Schomaker" <rupa@rupa.com>
To: <freeswitch-users@lists.freeswitch.org>
Sent: Friday, September 18, 2009 11:07 AM
Subject: Re: [Freeswitch-users] mod_lcr and indexes

[rupa at rupa.com]

On Fri, Sep 18, 2009 at 9:47 AM, Marcelo Sosa - LST
<listas@askterisk.com> wrote:

[listas at askterisk.com]

Hello,

[rupa at rupa.com]

On Fri, Sep 18, 2009 at 11:31 AM, Marcelo Sosa - LST
<listas@askterisk.com> wrote: