Re: Performance Improvement in SQL

On Thu, Mar 10, 2016 at 7:44 AM, Lucas Souza Cruz <souzacruz001(at)gmail(dot)com>
wrote:

> Hi, my name is Lucas Souza and i live in Goiânia, Brazil.
> Recently, i had a problem with an SQL due to delay.
>
> The part of the SQL that was slow is: ' WHERE idprod = 123456 '.
>
> In this line, the execution was of fifteen seconds.
>
> And i try this: ' WHERE CASE WHEN idprod = 123456 THEN TRUE ELSE FALSE END
> = TRUE '.
>
> Now, the execution was half of one second.
>
>
> I sending this e-mail because i believe that the PostgreSQL Community can
> improvement the perfomance of database
>
> If this solution exists, sorry for this e-mail.
>
> And sorry too for my english.
>
>
​Thanks for the report but there isn't enough information here to do
anything with - and given the nature of the complaint if there actually was
an issue that caused your described behavior I am positive we would have
heard about it. I'm chalking it up to "solar flares at the time the first
query was run" - but if you can construct something repeatable, on a
current version of PostgreSQL (9.1-5.x=most recent point release), and show
actual system generated evidence (namely, "explain analyze" output)

​then maybe this report can be given attention.

And regardless you should read the following as a start for how to
formulate this kind of request:

http://www.postgresql.org/docs/current/static/bug-reporting.html
https://wiki.postgresql.org/wiki/Slow_Query_Questions

David J.
​