LAST_INSERT_ID using triggers the safe way

[Kosta Psimoulis]

Hello,

Since triggers do not remember the last_insert_id updates, I created a trigger, a function and a lua script to handle that. I am gonna be doing rw splitting using the proxy-read-only-backend-addresses option. I know that there has been some modifications in the code to handle LAST_INSERT_ID calls to go through the same backend.
My question basically is, would the following script affect the modifications that have been done in mysql-proxy to handle this and how would the rw splitting work if I use the proxy-read-only-backend-addresses option ? Would it automatically read the script from /usr/share/mysql-proxy/rw-splitting.lua ? And between that script and my proxy-lua-script which one would have priority ?

trigger code

CREATE TRIGGER `t1_insert_after_trigger` AFTER INSERT ON `t1` FOR EACH ROW BEGIN
    INSERT INTO t2(name,address) VALUES(NEW.username,NEW.email);
    set @trigger_last_insert_id := (select last_insert_id());
END;

function code

CREATE FUNCTION `TRIGGER_LAST_INSERT_ID`() RETURNS int(11)
BEGIN
  DECLARE t_id INT;
  IF @trigger_last_insert_id IS NULL THEN
    SET t_id = 0;
  ELSE
    SET t_id = @trigger_last_insert_id;
  END IF;
  RETURN (t_id);
END

lua code

function read_query( packet )
   if string.byte(packet) == proxy.COM_QUERY then
     local query = string.sub(packet, 2)
     local replacing = false
     if string.match(string.upper(query), 'LAST_INSERT_ID') then
         query = string.gsub(query,'LAST_INSERT_ID', 'TRIGGER_LAST_INSERT_ID')
         replacing = true
     end
     if (replacing) then
         proxy.queries:append(1, string.char(proxy.COM_QUERY) .. query )
         return proxy.PROXY_SEND_QUERY
     end
   end
end