Re: if exists / where exisyts.... - Mailing list pgsql-interfaces

From Ron Johnson
Subject Re: if exists / where exisyts....
Date
Msg-id 1022254332.2286.11.camel@rebel
Whole thread Raw
In response to if exists / where exisyts....  (Denis Cartier Millon <Denis.CM@Wanadoo.fr>)
List pgsql-interfaces
On Fri, 2002-05-24 at 09:12, Denis Cartier Millon wrote:
> i want to test if a table exists before to drop this......
> 
> the :
> if exists (select 1 from pg_tables where tablename = "thetable")
> drop table thetable
> ;
> 
> don't work....

I'd use the system catalogs:
test2=# select count(*) from pg_class where relname = 'foo';count 
-------    1
(1 row)

test2=# select count(*) from pg_class where relname = 'snaggle';count 
-------    0
(1 row)

You can use it for tables, views, indexes (and maybe other
things).

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