在SQLServer中,现有手机表Phone,包含字段:p__price(手机价格),p__id(手机编号),p__brand(手机品牌),计算每个品牌的手机数量,正确的SQL是()
A.SELECTp_brand,COUNT(p_id)FROMPhoneGROUPBYp_id
B.SELECTp_brand,COUNT(p_id)FROMPhoneGROUPBYp_brand
C.SELECTp_brand,COUNT(p_id)FROMPhoneGROUPBYp_price
D.SELECTp_brand,COUNT(p_id)FROMPhoneORDERBYp_brand