Question

CREATE TRIGGER ATTENDANCE_INSERTION_TRIGGER
ON course_enrollment
AFTER INSERT
AS
BEGIN

--insert **what just was inserted in course_enrollment** into course_schedule_attendance

END
GO

如何参考在课程中插入的内容？

Answer 1

试试这个：

CREATE TRIGGER ATTENDANCE_INSERTION_TRIGGER 
ON course_enrollment 
AFTER INSERT 
AS 
BEGIN

  --insert **what just was inserted in course_enrollment** into
  -- course_schedule_attendance  
  INSERT course_schedule_attendance  
      (course_id, student_id)
    SELECT
      course_id, student_id --you could use: INSERTED.course, INSERTED.student_id
      FROM INSERTED
END 
GO

您也可以在单个INSERT中执行此操作，不使用触发器：

--insert a single row in both tables at one time
INSERT course_enrollment 
      (course_id, student_id)
      OUTPUT course_id, student_id INTO course_schedule_attendance  
   VALUES (@xyz, @abc)

--or insert a set of rows into both at one time
INSERT course_enrollment 
      (course_id, student_id)
      OUTPUT course_id, student_id INTO course_schedule_attendance  
   SELECT
       xyz, abc
       FROM ...

Answer 2

您可以从插入的表中获取值

SELECT * FROM INSERTED I

例如，如果course_enrollment有一个名为course_id和student_id的字段，那么为了获得这些字段，你可以做一个

SELECT I.course_id,I.student_id FROM INSERTED I -- I is just an alias and is not needed but it helps

Answer 3

有两个有用的触发器元表，它们都与触发器所在表的模式匹配，INSERTED和DELETED。

有趣的是，如果运行更新语句，触发器元表将包含INSERTED和DELETED中的行，DELETED行对应于“更新前”，INSERTED对应“更新后”。

这也使其有助于审计目的。

如何引用刚刚插入的值（在TRIGGER语句中）？

3 个答案: