表關聯使用INNER JOIN實現更新功能

準備一些數據，創建2張表，表1為學生表：

CREATE TABLE [dbo].[Student]
(
    [SNO] INT NOT NULL PRIMARY KEY,
    [Name] NVARCHAR(10) NOT NULL,
    [Performance] DECIMAL(18,2) NULL
)

GO

表2為學生成績表：

接下來，我們為上面2張表添加一些數據，並查詢數據結果：

INSERT INTO [dbo].[Student]([SNO],[Name])
VALUES  
(10001,N'甲'),
(10002,N'乙'),
(10003,N'丙'),
(10004,N'丁'),
(10005,N'戊'),
(10006,N'已'),
(10007,N'庚')
GO

INSERT INTO [dbo].[Performance]([SNO],[Score]) 
VALUES 
(10002,320),
(10004,380),
(10001,424),
(10007,467),
(10005,300)
GO

SELECT * FROM [dbo].[Student]
GO

SELECT * FROM [dbo].[Performance]
GO

以上均是為本篇所準備的數據。

把表2的欄位[Score]值更新至表1的[Performance]。

UPDATE s
SET s.[Performance] = p.[Score]
FROM [dbo].[Student] AS s
INNER JOIN [dbo].[Performance] AS p ON(s.[SNO] = p.[SNO])
GO

SELECT * FROM [dbo].[Student]
GO