MySQL how to join tables on two fields

Solution 1:

JOIN t2 ON t1.id=t2.id AND t1.date=t2.date

Solution 2:

JOIN t2 ON (t2.id = t1.id AND t2.date = t1.date)

Solution 3:

SELECT * 
FROM t1
JOIN t2 USING (id, date)

perhaps you'll need to use INNEER JOIN or where t2.id is not null if you want results only matching both conditions