我有如下表格:
Customer(CustomerID, UserName, Email, CustomerType)
CustomerVisit(CustomerVisitID, CustomerID, VisitDateTime, VisitLength)
Product(ProductCode, ProductName, ProductDescription, QuantityInStock, UnitPrice)
ProductView(CustomerVisitID, ProductCode, AddedToBasket)
我的命令如下
select customerid, customervisitid, count(customervisitid)
from customer_aqd, productview_aqd
group by customerid, customervisitid
我知道如何在不重复customervisitid
的情况下代表使用customerid
和customersid
查看过的所有商品,因为我不希望任何人没有任何productview
数据。
所以,为了清楚起见,我只希望能够看到表格中有productview
的客户,看看他们customervisits
<{}有多少customerid
< em>但仅限于他们拥有productview
数据。
答案 0 :(得分:0)
Inner join
CustomerVisit_aqd
表到ProductView_aqd
表:
select cv.customerid, cv.customervisitid, count(cv.customervisitid)
from productview_aqd p
inner join customervisit_aqd cv on cv.CustomerVisitID = p.CustomerVisitID
group by cv.customerid, cv.customervisitid