On Mon, 21 Nov 2005, Bartosz Jakubiak wrote: > Hi. > > I'm new with PostgreSQL, but this thing doesn't allow me to sleep: > > I wonder if it is possible to execute SQL query which: > 1. checks out if table exists, and if it is: > 2. deletes it > All of it at SQL query level, preferrably in one transaction. > > Something like (MSSQL): > IF EXISTS (SELECT * FROM sysobjects WHERE id = > object_id(n'properties_branches') AND objectproperty(id, n'isusertable') > = 1) > DROP TABLE properties_branches > > or (MySQL) > DROP TABLE IF EXISTS properties_branches; > This quite looks like rewrite a script auto generated from SQL Server :-) Yes, you can do that by querying the system catalog to see if a table exists (pg_class). However, notice there is possible a race condition here: if you found one table exists, but when you delete it, it may already deleted by others. Regards, Qingqing
