Kopiera MySQL-data och skapa en ny post med ett villkor

du var nära nog. ändra bara new till combined .

INSERT INTO combined (ip, user_ID)
SELECT  old.ip, new.user_ID
FROM    old
        INNER JOIN new 
            on old.email = new.email;

UPPDATERING 1

INSERT INTO combined (ip, user_ID, status)
SELECT  old.ip, new.user_ID, 'approved'
FROM    old
        INNER JOIN new 
            on old.email = new.email;