触发删除表中的先前重复记录

Question

我需要根据以下条件编写触发器

在表中插入记录之前，我需要将一列的值与现有记录进行比较，如果找到记录，则需要删除已存在记录中具有相同列值的记录，然后需要插入新记录。

请告诉我如何实现这一目标。

由于

Answer 1

CREATE TRIGGER [dbo].[CustomInsert_Trigger] ON [dbo].[Realtimebookingcount] INSTEAD OF INSERT AS BEGIN DECLARE @Flag INT SELECT @Flag = Booking_NUM FROM inserted IF (SELECT COUNT(1) FROM Realtimebookingcount WHERE Booking_NUM = @Flag) > 0 BEGIN DELETE FROM Realtimebookingcount WHERE Realtimebookingcount.Booking_NUM = @Flag END INSERT INTO Realtimebookingcount SELECT * FROM inserted END