Hello
On 05/04/2008, Guillaume Bog <guibog@gmail.com> wrote:
> Hello,
>
> I'm writing a trigger in pl/pgSQL and I'd like to pass one column name as
> argument to the trigger function.
>
> Provided my table has only one column named 'id', I can do easilly
>
> CREATE FUNCTION ft() RETURNS trigger AS $$
> BEGIN
> RAISE NOTICE 'It works:%', OLD.id;
> END
> $$ LANGUAGE plpgsql;
>
> But I'd like to do
>
> CREATE FUNCTION ft() RETURNS trigger AS $$
> DECLARE
> col VARCHAR;
> BEGIN
> col = TG_ARGV[0]
> RAISE NOTICE 'This does not works:%', OLD.col
> RAISE NOTICE 'This also does not works:%', OLD[col]
> END
> $$ LANGUAGE plpgsql;
>
> I tried OLD.(col) and other tricks, like "SELECT INTO" or "EXECUTE", and I
> checked the docs.
It's not possible in plpgsql. You have to use plperl, pltcl or plpython.
Regards
Pavel Stehule
>
>
