mysql - 如何获取触发器的插入值

Question

我正在尝试在 mysql 中创建一个触发器，当表上发生插入时，该触发器将插入到另一个表中。

CREATE TRIGGER addCardForNewUser AFTER INSERT ON swiped.Users
FOR EACH ROW
  BEGIN
      INSERT INTO swiped.Card (userid) VALUES (get value from original insert here);
  END

在插入语句的值部分中，我如何从原始插入中获取值以在此处使用？

谢谢

Answer 1

您可以将这些值与new.columnname一起使用。如果列的名称也是userid，那么您可以使用:

CREATE TRIGGER addCardForNewUser AFTER INSERT ON swiped.Users
FOR EACH ROW
  BEGIN
      INSERT INTO swiped.Card (userid) VALUES (new.userid);
  END

来自official documentation :

Within the trigger body, the OLD and NEW keywords enable you to access columns in the rows affected by a trigger. OLD and NEW are MySQL extensions to triggers; they are not case sensitive.

In an INSERT trigger, only NEW.col_name can be used