MySQL to return the current timestamp + milliseconds

CURRENT_TIME_MILLIS.sql

CREATE FUNCTION CURRENT_TIME_MILLIS ()
RETURNS BIGINT
LANGUAGE SQL
SQL SECURITY INVOKER
BEGIN
   DECLARE _time BIGINT;

   select conv(concat(substring(uid,16,3), substring(uid,10,4), substring(uid,1,8)), 16,10)
      div 10000 - (141427 * 24 * 60 * 60 * 1000) into _time
   from (select uuid() uid) as alias;
   
   return _time;
END;