Subject: Recursive SETOF function
From: Richard Rowell <richard@bowmansystems.com>
To: pgsql-sql@postgresql.org
Content-Type: text/plain
Date: Mon, 22 Nov 2004 09:18:13 -0600
Message-Id: <1101136693.18148.66.camel@richard>
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I'm trying to port some TSQL to PLPGSQL.  The DB has a table with a
recursive foreign key that represents a tree hierarchy.  I'm trying to
re-create a TSQL function that pulls out all the ancestors of a given
node in the hierarchy.

I'm rather new to PLSQL and I have several questions.

1.  In TSQL, I can assign a scalar to the result of query like so:
  SET @var1 = (SELECT foo FROM bar WHERE bar.uid=@var2)

How would I do this in PLSQL?

2.  In TSQL the "result table" can be inserted into manually.  IE:

CREATE FUNCTION foo () RETURNS @ttable TABLE( uid INTEGER) AS BEGIN 
	INSERT @ttable VALUES (1)
	RETURN
END

Is there a way to manually insert rows into the result table in PLSQL?


What follows is my TSQL function if that helps give context.  

CREATE FUNCTION svp_getparentproviderids (@child_provider INTEGER)
RETURNS @provider_ids TABLE ( uid INTEGER )
AS
BEGIN
    DECLARE @cid AS INTEGER
    IF (SELECT count(*) FROM providers WHERE uid =@child_provider) > 0
    BEGIN
	SET @cid = @child_provider
	WHILE @cid IS NOT NULL
	BEGIN
	    INSERT @provider_ids VALUES (@cid)
	    SET @cid = (SELECT parent_id FROM providers WHERE uid=@cid)
	END
    END
    RETURN
END

--