Include PHP $_SESSION var on INSERT, UPDATE & DELETE

I'm using Editor, and trying to find a way to make database actions include a PHP $_SESSION variable for the currently logged in user. I am using the PHP libraries provided with Editor. This is a multi-user web app where users manage their own records, so and I really need queries to look something like this...

INSERT INTO table (name, age, user_id)  VALUES ($name, $age, $_SESSION['user_id'])

Without hacking the PHP libraries, what are my options?

Note: "user_id" is a field I'm NOT exposing in DataTables.