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oracle ±Ê¼Ç V Ö®´¥·¢Æ÷ (TRIGGER)

 ´¥·¢Æ÷ trigger
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      Ðд¥·¢Æ÷£¬Óï¾ä´¥·¢Æ÷
Ðд¥·¢Æ÷ÓëÓï¾ä´¥·¢Æ÷µÄÇø±ð£º
Ðд¥·¢Æ÷ÒªÇóµ±Ò»¸ö DML Óï¾ä²Ù×÷Ó°ÏìÊý¾Ý¿âÖеĶàÐÐÊý¾Ýʱ£¬¶ÔÓÚÆäÖеÄÿ¸öÊý¾ÝÐУ¬Ö»ÒªËüÃÇ·ûºÏ´¥·¢Ô¼ÊøÌõ¼þ£¬¾ù¼¤»îÒ»´Î´¥·¢Æ÷,FOR EACH ROW Ñ¡Ïî˵Ã÷´¥·¢Æ÷ΪÐд¥·¢Æ÷£»
Óï¾ä´¥·¢Æ÷½«Õû¸öÓï¾ä²Ù×÷ ×÷Ϊ´¥·¢Ê¼þ£¬µ±ËüÃÇ·ûºÏÔ¼ÊøÌõ¼þʱ£¬¼¤»îÒ»´Î´¥·¢Æ÷
´´½¨Óï·¨:
create or replace trigger trigger_name
       before |after
       insert |delete | update |{[of column[,column ...]]
       on [schema.]table_name
 for each row
       [when condition]
 trigger_body;
eg(×ÐϸÌå»á):
create or replace trigger hello_tri
        before insert or delete or update on emp
        for each row
begin
       dbms_output.put_line('ÎÒÊÇ´¥·¢Æ÷£¡');
end;


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