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Date: Wed, 14 May 2008 16:36:21 -0400
From: Alvaro Herrera <alvherre@commandprompt.com>
To: Premil Agarwal <preagarw@gmail.com>
Cc: pgsql-interfaces@postgresql.org, pgsql-admin@postgresql.org
Subject: Re: Function's final statement must be a SELECT
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Premil Agarwal escribió:
> I am trying to write a function in PgAdmin 1.8.2 for postgres 8.3. The
> function should check the input parameter for NULL. If its NULL then
> function should return 'Auto' otherwise return the input as such.

> 
> CREATE FUNCTION check_for_null( inp character varying) RETURNS character
> varying AS $$
[...]
> $$ LANGUAGE SQL;

              ^^^

There's your problem.  Try using PLPGSQL instead.

In any case, you can do this with COALESCE() and it's much easier.

-- 
Alvaro Herrera                                http://www.CommandPrompt.com/
The PostgreSQL Company - Command Prompt, Inc.