Re: Generic Function
От
George Weaver
Тема
Re: Generic Function
Дата
Msg-id
004b01c52954$dacb5ec0$6400a8c0@Dell4500
Список
Дерево обсуждения
Generic Function lucas@presserv.org
----- Original Message -----
From:
To:
Sent: Monday, March 14, 2005 12:15 PM
Subject: [SQL] Generic Function
> Hi,
> Can I built a generic function like:
> CREATE FUNCTION f (text) RETURNS TEXT as
> $$
> return 'select * from $1';
> $$
> I know its impossible as writed. Also I have looked for EXECUTE procedure
> but it
> not run the correct function.
If you show us what you've tried and the results you received we may be able
to help more.
Some points:
1. To create a string to run with EXECUTE you would need to concatenate
the above phrase:
(Assuming "query" has been declared as text): query := 'Select *
from ' || $1;
2. Since you're likely returning multiple rows, you need to write your
function as a set-returning function. See:
http://www.postgresql.org/docs/8.0/static/plpgsql-control-structures.html#PLPGSQL-RECORDS-ITERATING
and Executing Dynamic Commands in
http://www.postgresql.org/docs/8.0/static/plpgsql-statements.html#PLPGSQL-STATEMENTS-PERFORM
> Is there a way to construct this clause? Using plpgsql/pltcl/anything....
> ???
>
> Thanks
>
> ---------------------------(end of broadcast)---------------------------
> TIP 5: Have you checked our extensive FAQ?
>
> http://www.postgresql.org/docs/faq
>
В списке pgsql-sql по дате отправления