Re: statement stuck when the connection grew up to 45 or more

I had check using ps -auxw|grep postgres & using select * from
pg_stat_activity
and it shows that the is really running and use 99% of the CPU.

Is there any wrong with the query?
As suggested by Jan Cruz, it is to fine tune the performance of the query.
Even if I not fine tune the query it should able to run without problem.

What I not understand is why this query stuck when the connection growth up
to certain limit.

I did try execute the query with the connection more than 45 and it really
stuck there.
I wait for around 10 minutes but it still running.
I kill about 10 connections then the query start to run and finish within
30 sec.

May I know what will be the possible cause of this problem?

Regards,
KH Ang




                  
                      "Jan Cruz"
                  
                      <malebug@gmail.com>         To:       "Qingqing Zhou" <zhouqq@cs.toronto.edu>
                  
                      Sent by:                    cc:       pgsql-bugs@postgresql.org
                  
                      pgsql-bugs-owner@pos        Subject:  Re: [BUGS] statement stuck when the connection grew up to
45or more           
                      tgresql.org
                  

                  

                  
                      06/02/2006 03:08 PM
                  

                  

                  




This is the statement which having problem:
     select count(distinct empno) as counter1 from pay_master_history
           where empno in (select empno from pay_batch_basic_history where
organizationid like '015003%')
     and processyear = '2006'
     and processmonth = '05'
     and processbatch = '1'

SELECT COUNT (*) FROM (
SELECT empno as counter1 from pay_master_history as a
INNER JOIN (select empno from pay_batch_basic_history where organizationid
like '015003%'      and processyear = '2006'
     and processmonth = '05'
     and processbatch = '1') as b
ON b.empno = a.empno ) as count_result
-----------------------------
or just create the view and use inner join then count :b