Re: How to create trigger after update on the simple slide

On Mon, 22 Oct 2007 08:55:14 -0700, "fitzjarrell_at_cox.net" <fitzjarrell_at_cox.net> wrote:

>On Oct 22, 9:19 am, Brian Tkatch <N/A> wrote:
>> On Sun, 21 Oct 2007 18:41:57 -0700, Krista <ywa..._at_gmail.com> wrote:
>> >Hi everyone,
>>
>> >I am practice on create trigger in Oracle. I found some simples online
>> >and tried to put it in my computer. However, it pops up an error
>> >messge "warning: trigger created with compilation errors."
>>
>> >Question: we want the net worth of any executive to be below $50000.
>>
>> >First i created the table:
>> >create table movieexce(name varchar2(50) primary key, address
>> >varchar2(50), networth number(9,2));
>>
>> >Second i tried to create trigger: ( actually, i put the same thing on
>> >the net to test it)
>> >create or replace trigger avgnetworthafterupdate
>> >after update of networth on movieexce
>> >referencing
>> > old as oldstuff
>> > new as newstuff
>> >begin
>> >if (50000>(select avg(networth) from movieexce)) then
>> > delete from movieexce where (name, address, networth) in newstuff;
>> > insert into movieexce (select * from oldstuff);
>> >end if;
>> >end avgnetworthafterupdate;
>> >/
>> >Result:warning: trigger created with compilation errors.
>>
>> >any one has clue what is wrong with that trigger?
>>
>> >Thanks,
>> >Krista
>>
>> Why use a TRIGGER? Perhaps a CONSTRAINT can be ADDed to the TABLE to
>> only only less then that salary.
>>
>> ALTER TABLE MovieExec ADD CONSTRAINT xxx CHECK (NetWorth < 50000);
>>
>> This way the record is rejected with an error, as opposed to secretly
>> changed.
>>
>> B.- Hide quoted text -
>>
>> - Show quoted text -
>
>It depends, really, on the goal the instructor has set and which tools
>are available to meet that goal. Both are valid 'solutions' to the
>basic problem, however we know nothing of the specifics of
>implementation the instructor has set forth. The OP is learning how
>to write triggers as stated in the original post; I expect that's the
>solution with which she's expecting assistance.
>
>
>David Fitzjarrell

Ah, i see. I thought "I am practice on create trigger in Oracle." meant that she was trying to learn to use TRIGGERs because she thought ti was the solution to her problem. Not that she specifically wanted to use a TRIGGER.

Oh well. :)

B. Received on Tue Oct 23 2007 - 09:08:19 CDT