Hi Thom, Thank you for your response. I have a application which is periodically gathering diff stats from diff devices and put them into database. Tables are created per stat, per device and per day. e.g. stat1_dev1_20100125, stat1_dev1_20100126, stat1_dev1_20100127, etc. stat1_dev2_20100125, stat1_dev2_20100126, stat1_dev2_20100127, etc. stat2_dev1_20100125, stat2_dev1_20100126, stat2_dev1_20100127, etc. stat2_dev2_20100125, stat2_dev2_20100126, stat2_dev2_20100127, etc. Now when I am upgrading my application with new version then there are some tables which are having some additional columns. In this case I have to alter each and every old tables in database with new column and it's default value. As there are large number of tables, the upgrade process is taking too much time (in days). To avoid above upgrade process I want to write a SQL statements such that it take care of newly added columns. Thanks, Santosh. -----Original Message----- From: Thom Brown [mailto:thom@xxxxxxxxx] Sent: Thursday, January 27, 2011 3:09 PM To: Santosh Bhujbal (sabhujba) Cc: pgsql-sql@xxxxxxxxxxxxxx; pgsql-general@xxxxxxxxxxxxxx Subject: Re: Queyring for columns which are exist in table. On 27 January 2011 07:52, Santosh Bhujbal (sabhujba) <sabhujba@xxxxxxxxx> wrote: > Hi All, > > > > I want to fire a query such that if the particular column does not exist > then query should return some default value. Why do you want to do this? What is it you using this for? -- Thom Brown Twitter: @darkixion IRC (freenode): dark_ixion Registered Linux user: #516935 -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general