多项选择题
现有订单表orders,包含数据如下表。若查询既订购了产品p01,又订购了产品p02的顾客编号,可以执行以下()sql语句。(选择两项)
A.select distinct (cid) from orders ol where ol.pid in ('p01','p02')
B.select distinct (cid) from orders ol where ol.pid = 'p01' and ol.pid = 'p02
C.select distinct (o1.cid) from orders o1,orders o2 where o1.pid='p01' and o2.pid='p02' and o2.cid = o1.cid
D.select distinct(cid) from orders where pid = 'p01' and cid in(select cid from orders where pid='p02')