Question

基本上我想将所有已更新的行复制到另一个SQL历史记录表中，但要附加“版本”列

CREATE TRIGGER [dbo].TriggerName 
ON [dbo].[Users] 
AFTER UPDATE 
AS
BEGIN
    SET NOCOUNT ON;

    INSERT INTO [dbo].[UsersHistory] ([AspNetUserId], [CreditCustomerId],
                                      [UserName], [GivenNames], [Surname],
                                      [Email], [PhoneNumber], [Active],
                                      [Administrator], [AutomaticSuspension],
                                      [CurrentVersion], [Version], [Notes],
                                      [LastUpdateId], [LastUpdateDate])
        SELECT 
            Id, CreditCustomerId, 
            UserName, GivenNames, Surname, 
            Email, PhoneNumber, Active, 
            Administrator, AutomaticSuspension,
            1,
            (SELECT ISNULL(MAX(VERSION) + 1, 1) 
             FROM [dbo].AspNetUsersHistory
             WHERE AspNetUserId = (SELECT Id from DELETED)),
            Notes,
            0, GETDATE()
        FROM 
            DELETED
END

如果这样做，我会在下面出现错误

子查询返回了多个值。当子查询遵循=，！=，<，<=，>，> =
时，不允许这样做

基本上，我想为每个用户更新版本列，因此每当用户更改详细信息时，它应该为1,2或3。

Answer 1

更改

(SELECT ISNULL(MAX(VERSION) + 1, 1) from [dbo].AspNetUsersHistory
WHERE AspNetUserId = (SELECT Id from DELETED)),

到

(SELECT ISNULL(MAX(VERSION) + 1, 1) from [dbo].AspNetUsersHistory
WHERE AspNetUserId = deleted.ID),

不需要（从已删除的ID中选择）-这是一个子查询，它可以直接看到正在处理的父行。

编辑后添加

要更新记录的所有先前版本以将CurrentVersion设置为false，请将其置于插入上方的触发器内-它应首先运行

UPDATE UH SET CurrentVersion = 0
FROM dbo.[UsersHistory] UH
    INNER JOIN deleted D on D.Id = UH.[AspNetUserId]
WHERE UH.CurrentVersion <> 0;

Answer 2

您需要记住，特殊表Deleted将不仅包含一行，而且包含触发更新语句一部分的完整行集。因此，如果您在一条语句中更新10行，则DELETED表中将包含10行。这是您的WHERE AspNetUserId = (SELECT Id from DELETED))失败的地方。我倾向于将它们全部带有时间戳记写在历史记录表中，如果以后需要转换为版本号，请稍后使用查询。用这种方式完成的版本号总是有问题的。

Answer 3

您不应在派生表中再有一条SELECT语句。只需使用SELECT语句中的ID，如下所示：

INSERT INTO [dbo].[UsersHistory] ([AspNetUserId], [CreditCustomerId],
                                      [UserName], [GivenNames], [Surname],
                                      [Email], [PhoneNumber], [Active],
                                      [Administrator], [AutomaticSuspension],
                                      [CurrentVersion], [Version], [Notes],
                                      [LastUpdateId], [LastUpdateDate])
SELECT 
            Id, CreditCustomerId, 
            UserName, GivenNames, Surname, 
            Email, PhoneNumber, Active, 
            Administrator, AutomaticSuspension,
            1,
            (SELECT ISNULL(MAX(VERSION) + 1, 1) 
             FROM [dbo].AspNetUsersHistory
             WHERE AspNetUserId = d.Id),
            Notes,
            0, GETDATE()
        FROM 
            DELETED as d;

SQL Server触发器可将更新的行复制到另一个历史表

3 个答案: