Question

我不知道代码如何引发错误。它正确编译但在使用它时会引发错误。

create or replace TRIGGER TRG_APPLICATIONS
BEFORE INSERT or UPDATE OF APP_ID, STATUS_ID
ON APPLICATIONS
FOR EACH ROW
BEGIN

:new.APP_ID := SEQ_APP_ID.nextval;
:new.APP_DATE := SYSDATE;

IF UPDATING AND ( :NEW.STATUS_ID = 2 OR :NEW.STATUS_ID = 5 OR :NEW.STATUS_ID = 7 OR :NEW.STATUS_ID = 8 )
THEN
   INSERT INTO APP_HISTORY (SRN, STATUS_ID, APP_DATE)
   VALUES (:OLD.SRN, :OLD.STATUS_ID, :OLD.APP_DATE);       

       DELETE FROM APPLICATIONS    WHERE :NEW.STATUS_ID = 2;
       DELETE FROM APPLICATIONS    WHERE :NEW.STATUS_ID = 5;
       DELETE FROM APPLICATIONS    WHERE :NEW.STATUS_ID = 7;
       DELETE FROM APPLICATIONS    WHERE :NEW.STATUS_ID = 8;

END IF;

END;

这是错误消息

error ORA-04091: table APEX514.APPLICATIONS is mutating, 
trigger/function may not see it ORA-06512: at "APEX514.TRG_APPLICATIONS", 
line 14 ORA-04088: error during execution of trigger 'APEX514.TRG_APPLICATIONS'

Answer 1

变异表错误的最可能原因是滥用触发器。这是一个典型的例子： 1.你在表A中插入一行

2.表A上的触发器（对于每一行）在表A上执行查询，例如计算汇总列

3.Oracle抛出一个ORA-04091：表A正在变异，触发器/函数可能看不到它

进一步阅读的来源。 http://dba.stackexchange.com/questions/5432/what-are-the-causes-and-solutions-for-mutating-table-errors

在触发器中删除代码抛出错误oracle

1 个答案: