Anda cukup dekat. ganti saja new
menjadi combined
.
INSERT INTO combined (ip, user_ID)
SELECT old.ip, new.user_ID
FROM old
INNER JOIN new
on old.email = new.email;
PERBARUI 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;