Very simple - you can't. The rule is you can't read (select)
from the table you have the trigger on.
> I have a table t1.
> Create table t1(
> CostName Char(10),
> Cost Number(12,2) default 0,
> AllCost Number(12,2) default 0
> );
> I Want to use Trigger to set AllCost = sum(Cost) by CostName.
> I use "after insert for each row" and get mutating error!
>
> How to write this trigger!
> or some better ways to realise this function.
>
> eg:
> Insert 'abc',1
> the result 'abc',1,1
> insert 'abc',2
> the result 'abc',1,3
> 'abc',2,3
> insert 'abc',1
> the result 'abc',1,4
> 'abc',2,4
> 'abc',1,4
>
>
>
> Sent via Deja.com http://www.deja.com/
> Before you buy.
>
>
--
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Received on Mon Dec 13 1999 - 09:53:37 CST
