假设“订单”表中有订单号、职员号、客户号和金额字段,正确的SQL语句只能是( )。
A.
SELECT 职员号 FROM 订单; GROUP BY 职员号 HAVING COUNT(*)>3 AND AVG_金额>200
B.
SELECT 职员号 FROM 订单; GROUP BY 职员号 HAVING COUNT(*)>3 AND AVG(金额)>200
C.
SELECT 职员号 FROM 订单; GROUP,BY 职员号 HAVING COUNT(*)>3 WHERE AVG(金额)>200
D.
SELECT 职员号 FROM 订单; GROUP BY 职员号 WHERE COUNT(*)>3 AND AVG_金额>200