CREATE FUNCTION rubric_delete_leaf (text)
RETURNS boolean
AS '
DECLARE
id ALIAS FOR $1;
rubric RECORD;
BEGIN
SELECT rubric_left AS lft, rubric_right AS rght INTO rubric FROM rubrics WHERE rubric_id = id;
IF NOT FOUND THEN
RAISE EXCEPTION ''cannot find rubric (ID %)'', id;
END IF;
IF rubric.rght - rubric.lft > 1 THEN
RAISE EXCEPTION ''rubric (ID %) has child rubrics, cannot delete'', id;
END IF;
DELETE FROM rubrics WHERE rubric_id = id;
UPDATE rubrics SET rubric_left = rubric_left - 2 WHERE rubric_left > rubric.rght;
UPDATE rubrics SET rubric_right = rubric_right - 2 WHERE rubric_right >= rubric.rght;
RETURN ''t'';
END;
' LANGUAGE 'plpgsql';
(((
