Re: dblink performance

Bruno Lavoie <bruno.lavoie@xxxxxxxxx> · Wed, 07 Dec 2011 15:52:41 -0500



    Le 2011-12-07 11:14, Alex Bible a écrit :
    
      
        Hello All,
        I’m currently on a development team
          utilizing PostgreSQL and we are looking into the possibility
          of using dblink to reference an external database (read only).
          Our system administrator and DBA were concerned about the
          performance impact that cross-database queries would have on a
          production application. Are there any known performance issues
          or anything of the like that I would need to know before
          pushing this issue further? I have been using PostgreSQL for
          the past couple months but this is my first time using dblink.
          I really just need an opinion from someone who has used this
          technology before. Thanks!
         
        
          Alexander
              E. Bible

              
    Hello,

    
    one problem is when you join local data with remote data. The
    optimizer falls short on this when finding good plans and executing.
    If you frequently need to join with non-volatile remote data, it's
    generally better to make a snapshot of remote tables. It all depends
    on volume and usage patterns of databases.

    
    Interesting link:

    http://www.postgresonline.com/journal/archives/44-Using-DbLink-to-access-other-PostgreSQL-Databases-and-Servers.html

    
    hope that's help

    Bruno Lavoie

    bl@xxxxxxxxxx

    bruno.lavoie@xxxxxxxxx