Re: What happens between end of explain analyze and end of query execution ?

Franck Routier <franck.routier@xxxxxxxxx> · Sat, 06 Apr 2013 10:13:37 +0200



    Le 05/04/2013 16:18, Nikolas Everett a
      écrit :

    
      On Fri, Apr 5, 2013 at 9:55 AM, Franck Routier <franck.routier@xxxxxxxxx>
        wrote:

        
            Le
              04/04/2013 21:08, Tom Lane a écrit :

              Maybe the statistics tables for sandia and saneds are in a
              bad shape ? (don't know how to check this).

              
              Regards,

              
              Franck

              
        Could this be caused by system
          table bloat?
        

        Also, can you check how long
          it takes to plan:
        1.  A query without a table at
          all (SELECT NOW())
        2.  A query with an unrelated
          table
        

          Again, what version of PostgreSQL is this?
      
    
    PG 8.4.8

    select now() is quick (15ms from pgadmin)

    But I can reproduce the problem on other tables : explain on a query
    with 4 join takes 4.5 seconds on an other set of tables...

    
    System bloat... maybe. Not sure how to check. But as Tom asked,
    default_statistics_target is 5000. Maybe the problem is here ? What
    should I look after in pg_statistic to tell is there is a prolem
    here ?

    
    Regards,

    Franck

  
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