Re: Trigger howto

Greg,

You can assign a value to new column only in the before row triggers. Assuming that start_date and exec_days can't be nulls:

create or replace
trigger my_trigger
before update or insert
on my_table
for each row
begin
  if inserting or updating then

     :new.EXEC_DATE := :new.START_DATE + :new.EXEC_DAYS;   end if;
end;

-- 
Regards,

Zbigniew Sliwa
Oracle Programmer
Poland
email: zibi_at_at_yahoo.com

Greg wrote:


> 

> I have a Table like


> 

> START_DATE          EXEC_DAYS       EXEC_DATE

> 15-OCT-00                -10                         5-OCT-00

> 

> Now I need a Trigger to update

> the EXEC_DATE when the START_DATE changes.

> 

> I tried

> 

>   create or replace

>   trigger my_trigger

>   after update or insert

>   on my_table

>   for each row

>   begin

>     if updating then

>        :new.EXEC_DATE := START_DATE + EXEC_DAYS;

>     end if;

>  end;

> 

> But can't use START_DATE and  EXEC_DAYS

> 

> tried  my_table.START_DATE also not worked

> 

> do I have to make a select for the START_DATE and  EXEC_DAYS

> but how to find the right row...

> 

> Found info's about updating other Tables but nothing

> about my problem.

> 

> Thanks for any help

> Greg