Re: Unused indexes - PostgreSQL 9.2 - Mailing list pgsql-general

From Melvin Davidson
Subject Re: Unused indexes - PostgreSQL 9.2
Date
Msg-id CANu8Fiyxb242kX=tNvPc2spQw7SoD=1rsST7vnW3hgScUn0DNA@mail.gmail.com
Whole thread Raw
In response to Re: Unused indexes - PostgreSQL 9.2  ("David G. Johnston" <david.g.johnston@gmail.com>)
List pgsql-general
Here is the url which explains the columns in pg_stat_all_indexes view
http://www.postgresql.org/docs/9.2/static/monitoring-stats.html#PG-STAT-ALL-INDEXES-VIEW

On Mon, May 23, 2016 at 8:42 PM, David G. Johnston <david.g.johnston@gmail.com> wrote:
On Mon, May 23, 2016 at 8:33 PM, Lucas Possamai <drum.lucas@gmail.com> wrote:


On 24 May 2016 at 12:18, Jeff Janes <jeff.janes@gmail.com> wrote:
On Mon, May 23, 2016 at 4:23 PM, Lucas Possamai <drum.lucas@gmail.com> wrote:
>
> That index has been added just 3 hours ago, and you can see that the
> times_used goes over 41000.... How is that possible??

Well, that is what it is there for, right , to be used?  My ancient
laptop can use an index that many times in less than 20 seconds,
running flat out.


Yeah!
But I mean... over 70.000 times in 4 hours? that's a lot of usage! ahhahaha
 
>
> Don't think the query is right.
>
> Can you please check ?

The query seems right to me.

Cheers,

Jeff

I think the query is ok.. just wanna understand if that value is correct :O

If it is.. I'm happy with that. Just shows the work of finding and creating the index worthed it.


​I don't have the answer off hand but what is it counting?  If it counts, say, each lookup into the index during a nested loop evaluation the difference in perception​ could be easily explained.

David J.




--
Melvin Davidson
I reserve the right to fantasize.  Whether or not you
wish to share my fantasy is entirely up to you.

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