触发器创建中的语法不正确

Question

我正在尝试在数据库中的一个表上创建触发器，如下所示

CREATE TRIGGER tr_JTIA_ForInsert
ON MyTable
FOR INSERT 
AS
BEGIN
    DECLARE @JTIItemID INT,
            @UserWWID INT

    IF EXISTS (SELECT * 
               FROM [MyTable] JTIA 
               INNER JOIN inserted NewItem ON NewItem.ItemID = JTIA.ItemID 
                                           AND NewItem.UserWWID = JTIA.UserWWID 
                                           AND NewItem.Status = JTIA.Status)
    BEGIN
        SELECT 
            @JTIItemID = inserted.ItemID, 
            @UserWWID = inserted.UserWWID 
        FROM
            inserted

        EXEC msdb.dbo.sp_send_dbmail
              @recipients = 'edwin@gmail.com', 
              @profile_name = 'App Administrator',
              @body = SELECT CONCAT('User : ',(SELECT CONVERT(varchar(20),12345)), ' was assigned a duplicate JTIItemID: ', (SELECT CONVERT(varchar(20),1234567)), ' at timestamp: ', (select convert(varchar, getdate(), 22))),
              @subject = 'Duplicate record Was Assigned to user:'; 
    END
END

当我执行上述触发器时，我在创建时收到以下错误消息。

消息 156，级别 15，状态 1，过程 tr_JTIA_ForInsert，第 16 行 [批处理开始第 0 行]
关键字“SELECT”附近的语法不正确。

消息 137，级别 15，状态 1，过程 tr_JTIA_ForInsert，第 17 行 [批处理开始第 0 行]
必须声明标量变量“@subject”。

不知道我错过了什么

Answer 1

这是您需要的粗略修改示例。我没有桌子，所以我无法测试它，但我怀疑它非常接近。

CREATE TRIGGER tr_JTIA_ForInsert
ON dbo.MyTable
AFTER INSERT 
AS
BEGIN
    SET NOCOUNT ON;
    SET XACT_ABORT ON;

    DECLARE @JTIItemID int;
    DECLARE @UserWWID int;
    DECLARE @EmailBody nvarchar(max);

    DECLARE @EmailsToSend TABLE
    (
        EmailsToSendID int NOT NULL IDENTITY(1,1) PRIMARY KEY,
        JTIItemID int,
        UserWWID int
    );

    INSERT @EmailsToSend (JTIItemID, UserWWID)
    SELECT i.JTIItemID, i.UserWWID
    FROM inserted AS i
    INNER JOIN dbo.MyTable AS mt
    ON mt.ItemID = i.ItemID 
    AND mt.UserWWID = i.UserWWID
    AND mt.[Status] = i.[Status];

    DECLARE @Counter int = 1;
    WHILE @Counter <= (SELECT MAX(EmailsToSendID) FROM @EmailsToSend)
    BEGIN
        SELECT @JTIItemID = ets.JTIItemID,
               @UserWWID = ets.UserWWID
        FROM @EmailsToSend AS ets
        WHERE ets.EmailsToSendID = @Counter;

        SET @EmailBody = CONCAT(N'User : ',
                                (SELECT CONVERT(varchar(20),12345)), 
                                N' was assigned a duplicate JTIItemID: ', 
                                (SELECT CONVERT(varchar(20),1234567)), 
                                N' at timestamp: ', 
                                (SELECT convert(varchar, GETDATE(), 22)));

        EXEC msdb.dbo.sp_send_dbmail
              @recipients = N'edwin@gmail.com', 
              @profile_name = N'App Administrator',
              @body = @EmailBody,
              @subject = N'Duplicate record Was Assigned to user:'; 
        SET @Counter += 1;
    END;
END;
GO

希望对你有所帮助。