在聯接或位置內的條件有什么不同(表現、最佳實踐等.)在JOIN子句中添加條件與WHERE子句之間？例如.。-- Condition in JOINSELECT *FROM dbo.Customers AS CUSINNER JOIN dbo.Orders AS ORD
ON CUS.CustomerID = ORD.CustomerIDAND CUS.FirstName = 'John'-- Condition in WHERESELECT *FROM
dbo.Customers AS CUSINNER JOIN dbo.Orders AS ORD
ON CUS.CustomerID = ORD.CustomerIDWHERE CUS.FirstName = 'John'你喜歡哪一個(也許是為什么)？
3 回答
蕪湖不蕪
TA貢獻1796條經驗 獲得超7個贊
SELECT *FROM dbo.Customers AS CUS LEFT JOIN dbo.Orders AS ORD ON CUS.CustomerID = ORD.CustomerIDWHERE ORD.OrderDate >'20090515'SELECT *FROM dbo.Customers AS CUS LEFT JOIN dbo.Orders AS ORD ON CUS.CustomerID = ORD.CustomerIDAND ORD.OrderDate >'20090515'
SELECT *FROM dbo.Customers AS CUS LEFT JOIN dbo.Orders AS ORD ON CUS.CustomerID = ORD.CustomerIDWHERE ORD.OrderID is null
楊__羊羊
TA貢獻1943條經驗 獲得超7個贊
OUTER JOIN
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