Question

我尝试创建一个日期时间字段，只有在某个字段发生更改时才会自动更新当前时间。

似乎我有语法错误。

CREATE OR ALTER TRIGGER last_progress_date
ON wp_task_mgr
AFTER UPDATE  
AS BEGIN
   IF UPDATE (progress_percentage)
   SET last_progress_date = GETDATE()
END

Answer 1

为了将来参考，我在这里找到答案：

https://dba.stackexchange.com/questions/125203/simple-trigger-to-update-two-columns-in-one-table

MySQL查询：

DELIMITER //
CREATE TRIGGER trig_1 before insert
ON  <table_name> FOR EACH ROW
BEGIN

   IF   new.due_date is not null and new.end_date='' then
        set new.end_date=new.due_date;
   end if;
      IF   new.end_date is not null and new.due_date='' then
        set new.due_date=new.end_date;
   end if;

END;
//


DELIMITER //

CREATE TRIGGER trig_2 before update
ON  <table_name> FOR EACH ROW
BEGIN 

   IF   new.due_date <>old.due_date then
        set new.end_date=new.due_date;
   end if;
      IF   new.end_date <> old.end_date then
        set new.due_date=new.end_date;
   end if;

END;
//

编辑另一个时，更新一个mysql列

1 个答案: