SELECT zip_code
,sum(tab)
FROM (
SELECT Count(Pickup_location) AS tab
,l.zipcode
FROM booking b
INNER JOIN location l
ON b.pickup_location = l.Zip_Code
GROUP BY l.zip_Code
UNION
SELECT Count(destination) AS tab
,l.zipcode
FROM booking_destinations bd
INNER JOIN location l
ON bd.destination = l.Zip_Code
WHERE bd.SEQUENCE IN(1,2,3,4)
GROUP BY l.zip_Code
) as dum
GROUP BY zip_Code;