Question

我的查询完美无缺：

SELECT *
FROM Customer
WHERE SacCode IN
(
    SELECT SacCode
    FROM SacCode
    WHERE ResellerCorporateID = 392
    ORDER BY SacCode
)
AND CustomerID IN
(
    SELECT CxID
    FROM CustAppointments
    WHERE AppRoomID IN
    (
        SELECT AppRoomID
        FROM ClinicRooms
        WHERE ClinID IN
        (
                SELECT ClinID
                FROM AppClinics
                WHERE ClinDate >='20090101'
                AND ClinDate <='20091119'
        )
    )
)

但是，我需要查看ClinDate的值（在最后一个嵌套查询中），所以我被告知需要使用JOINS重新编写查询。

我不知道怎么样，有人可以帮忙吗？

感谢。

Answer 1

这是一个开始：

SELECT     *
FROM       Customer c
INNER JOIN CustAppointments ca ON ca.CxId = c.CustomerID
INNER JOIN ClinicRooms cr ON cr.AppRoomID = ca.AppRoomID
INNER JOIN AppClinics ac ON ac.ClinID = cr.ClinID
WHERE      ap.ClinDate BETWEEN '20090101' AND '20091119'
AND        SacCode IN (SELECT sc.SacCode 
                       FROM SacCode sc 
                       WHERE sc.ResellerCorporateID = 392)

这将允许您从AppClinics中选择列。

Answer 2

阅读此http://www.w3schools.com/Sql/sql_join.asp

在MySQL中使用JOINS

2 个答案: