Re: Performance issues while running select sql query

On Sun, Apr 29, 2018 at 7:48 PM, Justin Pryzby <pryzby(at)telsasoft(dot)com> wrote:

> On Sun, Apr 29, 2018 at 10:05:23AM +0530, Kaushal Shriyan wrote:
> > # SELECT serorgid,appname,sum(message_count) AS mtrc0,date_trunc('day',
> > client_received_start_timestamp at time zone '+5:30:0')::timestamp
> without
> > time zone AS time_unit FROM analytics."test.prod.fact" WHERE
> > client_received_start_timestamp >= '2018-3-28 18:30:0' AND
> > client_received_start_timestamp < '2018-4-11 18:30:0' AND ((apiproxy in
> > ('test-service' ) ) and (exchangeinstance != '(not set)' ) and
> (devemail
> > != 'test(at)example(dot)com' ) and (devemail != 'srk(at)example(dot)com' ) and
> > (devemail != 'abc(at)example(dot)com' ) and (devemail != 'xyz(at)example(dot)com' )
> and
> > (apistatus = 'Success' ) and (apiaction not in
> > ('LRN','finder','ManuallySelect' ) ) and (appname not in ('Mobile
> Connect
> > Developer Portal (Int(', 'MinskHBM', 'LondonHBM', 'SeoulHBM',
> 'MumbaiHBM',
> > 'NVirginiaHBM','SPauloHBM', 'Mobile Connect HeartBeat Monitor',
> > 'PDMAOpenSDKTest1', 'PDMAOpenSDKTest2', 'PDMASDKTest', 'APIHealth',
> > 'A1qaDemoApp','test', 'dublin o2o test tool', 'Test from John do not
> > provision' ) ) and (serorgid = 'aircel' )) GROUP BY
> > serorgid,appname,time_unit ORDER BY time_unit DESC LIMIT 14400 OFFSET 0;
>
> This table has inheritence children. Do they have constraints? On what
> column? Is constraint_exclusion enabled and working for that?
>
> It looks like test.prod.fact_624 is being read using index in under 1sec,
> and
> the rest using seq scan, taking 5-10sec.
>
> So what are the table+index definitions of the parent and childs (say
> fact_624
> and 631).
>
> Have the child tables been recently ANALYZE ?
> Also, have you manually ANALYZE the parent table?
>

Hi Justin,

This table has inheritence children. Do they have constraints? On what
column? Is constraint_exclusion enabled and working for that?

Answer :- Is there a way to find out?

So what are the table+index definitions of the parent and childs (say
fact_624
and 631).

Answer :- Is there a way to find out?

Have the child tables been recently ANALYZE ?
Answer :- I have not done anything and is there a way to find out.

Also, have you manually ANALYZE the parent table?
Answer :- Nope

Any help will be highly appreciable. I look forward to hearing from you.

Best Regards,

Kaushal