Re: [External] LIMIT not showing all results - Mailing list pgsql-general

From Tom Lane
Subject Re: [External] LIMIT not showing all results
Date
Msg-id 2871.1551804378@sss.pgh.pa.us
Whole thread Raw
In response to Re: [External] LIMIT not showing all results  (Casey Deccio <casey@deccio.net>)
Responses Re: [External] LIMIT not showing all results  (Vijaykumar Jain <vjain@opentable.com>)
List pgsql-general
Casey Deccio <casey@deccio.net> writes:
>> On Mar 5, 2019, at 9:15 AM, Vijaykumar Jain <vjain@opentable.com> wrote:
>> Can you run both the queries with
>> “explain analyze select ....” and paste the output.

> dnsviz=> explain analyze select id,name,date from analysis where name = 'foo' order by date desc limit 20;
   
>                                                                                                  QUERY PLAN
                                                     

                                                   
>
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
> ----------------------------------
                                                     
>  Limit  (cost=0.57..81.74 rows=20 width=31) (actual time=0.540..0.541 rows=1 loops=1)
                                                     
>    ->  Index Scan Backward using analysis_name_date_key on analysis  (cost=0.57..7760.25 rows=1912 width=31) (actual
> time=0.539..0.540 rows=1 loops=1)
                                                     
>          Index Cond: ((name)::text = 'foo'::text)
>  Planning time: 6.728 ms
>  Execution time: 0.587 ms
> (5 rows)

Hm, so possibly corruption in that index?  REINDEX might help.

            regards, tom lane


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