oracle ±Ê¼Ç V Ö®´¥·¢Æ÷ (TRIGGER)
´¥·¢Æ÷ trigger
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´´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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SQL> select ascii(’A’) A,ascii(’a’) a,ascii(’0’) zero,ascii(’ ’) space from dual;
A A ZERO SPACE
--------- --------- --------- ---------
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