1.83. reachablefromnode( integer, integer[] )

Function Properties

Language: PLPGSQL

Return Type: SET OF integer

ReachableFromNode(receiver, blacklist) Find all nodes that <receiver> can receive events from without using nodes in <blacklist> as a relay.

declare
	v_node alias for $1 ;
	v_blacklist alias for $2 ;
	v_ignore int4[] ;
	v_reachable_edge_last int4[] ;
	v_reachable_edge_new int4[] default '{}' ;
	v_server record ;
begin
	v_reachable_edge_last := array[v_node] ;
	v_ignore := v_blacklist || array[v_node] ;
	return next v_node ;
	while v_reachable_edge_last != '{}' loop
		v_reachable_edge_new := '{}' ;
		for v_server in select pa_server as no_id
			from sl_path
			where pa_client = ANY(v_reachable_edge_last) and pa_server != ALL(v_ignore)
		loop
			if v_server.no_id != ALL(v_ignore) then
				v_ignore := v_ignore || array[v_server.no_id] ;
				v_reachable_edge_new := v_reachable_edge_new || array[v_server.no_id] ;
				return next v_server.no_id ;
			end if ;
		end loop ;
		v_reachable_edge_last := v_reachable_edge_new ;
	end loop ;
	return ;
end ;