Move the CASE
expressions inside the aggregates. I've also switched to using SUM
rather than COUNT
- there is a COUNT
variant but it may display a warning about eliminating NULL
values that I'd rather avoid.
SELECT Merchant_Master.Merchant_ID,
SUM(CASE WHEN Coupon_Type_ID=1
THEN 1 ELSE 0 END) AS "Secret",
SUM(CASE WHEN Coupon_Type_ID=2
THEN 1 ELSE 0 END) AS "Hot"
FROM Coupon_Master
INNER JOIN Merchant_Master
ON Coupon_Master.Merchant_ID=Merchant_Master.Merchant_ID
GROUP BY
Merchant_Master.Merchant_ID