Обсуждение: How to check if a table exists from functions.

Maybe I am doing this the wrong way, but how do I check if a table exist?

This works from psql:

select relname
from pg_class
where relname = 'tablename'


But if I try to do the same from a PL/PGSQL stored procedure I get the 
following error message:

ERROR:  unexpected SELECT query in exec_stmt_execsql()

Isn't select's allowed from stored procedures?

Is there a more simple way to check if a table exists?

On Tue, 19 Jun 2001, Mikael Kjellstr�m wrote:

> 
> Maybe I am doing this the wrong way, but how do I check if a table exist?
> 
> This works from psql:
> 
> select
>   relname
> from
>   pg_class
> where
>   relname = 'tablename'
> 
> 
> But if I try to do the same from a PL/PGSQL stored procedure I get the 
> following error message:
> 
> ERROR:  unexpected SELECT query in exec_stmt_execsql()
> 
> Isn't select's allowed from stored procedures?

You'll want to use something like:
declarefoo name;
begin...select relname INTO foo from pg_class whererelname=''tablename'';...
end;