求每个交易所的平均单价的SQL语句是
A.SELECT交易所,avg(单价)FROMskGROUPBY单价 B.SELECT交易所,avg(单价)FROMskORDERBY单价 C.SELECT交易所,avg(单价)FROMskORDERBY交易所 D.SELECT交易所,avg(单价)FROMskGROUPBY交易所正确答案D
求每个交易所的平均单价的SQL语句是
A.SELECT交易所,avg(单价)FROMskGROUPBY单价 B.SELECT交易所,avg(单价)FROMskORDERBY单价 C.SELECT交易所,avg(单价)FROMskORDERBY交易所 D.SELECT交易所,avg(单价)FROMskGROUPBY交易所正确答案D