CREATE OR REPLACE FUNCTION get_nodes(node integer, nodes integer[])
  RETURNS integer[] AS
$BODY$
DECLARE
	current_node integer;
	row_data RECORD;
BEGIN
	FOR  row_data IN SELECT e1.id as n1, e2.id as n2 FROM link l
			    INNER JOIN snmp_ports s1 ON (s1.id = l.portid1)
			    INNER JOIN snmp_ports s2 ON (s2.id = l.portid2)
			    INNER JOIN equipment e1 ON (e1.id = s1.equipment)
			    INNER JOIN equipment e2 ON (e2.id = s2.equipment) 
			    WHERE e1.id = node or e2.id = node
			    LOOP
		
		IF row_data.n1=node THEN
			current_node := row_data.n2;
		ELSE
			current_node := row_data.n1;
		END IF;

		if NOT nodes @> ARRAY[current_node] THEN
			nodes := array_append(nodes, current_node);
			nodes := get_nodes(current_node, nodes);
		END IF;
	END LOOP;
	RETURN nodes;  
END
$BODY$
  LANGUAGE plpgsql VOLATILE

SELECT get_nodes(4840, '{}');

SELECT e1.id as n1, e2.id as n2 FROM link l
			    INNER JOIN snmp_ports s1 ON (s1.id = l.portid1)
			    INNER JOIN snmp_ports s2 ON (s2.id = l.portid2)
			    INNER JOIN equipment e1 ON (e1.id = s1.equipment)
			    INNER JOIN equipment e2 ON (e2.id = s2.equipment