CREATE OR REPLACE FUNCTION getNextId() RETURNS VARCHAR(200) AS
$BODY$

DECLARE
    mfId integer;
    rootDir varchar(50) := 'mfdata/';
    createDir text := 'mkdir --mode=777 -p mfdata';
    dir varchar(100);
BEGIN
    INSERT INTO copy.history(time) values(now()) RETURNING id INTO mfId;
    EXECUTE('COPY (SELECT 1) TO PROGRAM ' || quote_literal('mkdir --mode=777 -p mfdata '));
    RETURN 'mfdata' || mfId;
END;
$BODY$
LANGUAGE plpgsql;