Re: Generic Plans for Prepared Statement are 158155 times slowerthan Custom Plans - Mailing list pgsql-performance

From Tomas Vondra
Subject Re: Generic Plans for Prepared Statement are 158155 times slowerthan Custom Plans
Date
Msg-id 20190520221631.6i47hwyodfqdk2ym@development
Whole thread Raw
In response to Re: Re: Re: Generic Plans for Prepared Statement are 158155 timesslower than Custom Plans  (Deepak Somaiya <deepsom@yahoo.com>)
Responses RE: Re: Generic Plans for Prepared Statement are 158155 times slower thanCustom Plans
List pgsql-performance
On Mon, May 20, 2019 at 09:37:34PM +0000, Deepak Somaiya wrote:
> wow this is interesting! 
>@Tom, Bruce, David - Experts
>Any idea why would changing the datatype would cause so much degradation - this is even when plan remains the same
,datais same.
 
>Deepak
>    On Friday, May 17, 2019, 2:36:05 AM PDT, Naik, Sameer <Sameer_Naik@bmc.com> wrote:
>
>
>Deepak,
>
>I changed the datatype from citext to text and now everything works fine.
>
>The data distribution is same, plan is same, yet there is a huge performance degradation when citext is used instead
oftext.
 
>
>However the business case requires case insensitive string handling.
>
>I am looking forward to some expert advice here when dealing with citext data type.
>
> 

It's generally a good idea to share explain analyze output for both
versions of the query - both with citext and text.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services 



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