从Oracle触发到SQL SERVER

Question

嗨，我如何将这个触发器从oracle重写到sql server？

CREATE OR REPLACE TRIGGER COUNTER
BEFORE INSERT OR UPDATE OF some_column ON my_table
FOR EACH ROW
BEGIN

   :NEW.My_counter := :NEW.My_counter+1;
   :NEW.value := :NEW.value+1;

END;

谢谢您的帮助。

Answer 1

在这种情况下，Oracle绝对更优雅……您可以尝试以下方法：

CREATE TRIGGER counter_trigger
   ON my_table AFTER INSERT, UPDATE
AS
BEGIN 
   update t
   set t.my_counter +=1,
       t.value += 1
   from my_table t
   where exists ( -- restrict to inserted or updated rows ...
      select null
      from inserted i
      where i.Id = t.Id
   ) and (exists ( -- ... where the specific column was updated
           select null
           from deleted d
           where d.Id = t.Id
           and d.some_column <> t.some_column -- add some form of coalesce here if column is nullable.
          )
          or not exists ( -- ... or the whole row was inserted.
           select null
           from deleted d
           where d.Id = t.Id
         )
   );
END
GO

以上作出以下假设。 如果这些都不正确，则必须对代码进行一些调整：

• 您的表有一个名为Id的主键列。
• some_column不能为空。 如果是，请调整条件以解决空值。
• 您的数据库已将recursive triggers enabled设置设置为false 。 如果您不知道此设置，则可能还可以。

Answer 2

CREATE TRIGGER trig_update
ON <table_name> or <database_name>
Instead of INSERT, UPDATE, DELETE /*made this instead of as I see your saying Before*/
AS
Being
<your sql code>
end;