Re: plpgsql recursion

Can you post the recursion function that you use on this case to get out
the information from the table ?

Thanks,
Luis Sousa

Stefano Vita Finzi wrote:

>Greetings!
>I have a table like:
>
>node parent
> 1 2
> 2 3
> 3 4
>
>Since i traverse this table with a recursive function, i want to avoid
>infinite recursion loop. I have wrote a function to check that a new record
>does not create a circular dependency. The function i wrote is as follow:
>
>CREATE OR REPLACE FUNCTION dba_test(INTEGER,INTEGER) RETURNS TEXT AS '
> DECLARE
> traversing ALIAS FOR $1;
> testing ALIAS FOR $2;
> t_rec RECORD;
> BEGIN
> FOR t_rec IN SELECT node,parent FROM dba_test WHERE parent = traversing
>LOOP
> IF t_rec.node = testing THEN
> RETURN ''Circular'';
> ELSE
> PERFORM dba_test(t_rec.node,testing);
> END IF;
> END LOOP;
> RETURN ''ok'' || testing::text;
> END;
>' LANGUAGE 'plpgsql';
>
>I would use this function BEFORE inserting the new row. But if i try SELECT
>dba_test(4,1); i don't have the result i expect. Can i you give me an hint
>where am i wrong?
>
>Thank you!
>
>Stefano Vita Finzi
>kluge(at)despammed(dot)com
>
>
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