Re: update triggers to update same table

Hi.

 It is a wrong assumption.
 Actually Oracle keeps 2 sets of row values in memory  and you update in trigger the :new set of values ( if  it is BEFORE trigger ).
 On the other hand - Oracle will not allow you to execute  a trigger that access the same table which is currently  updated ( See MUTATING TABLE in APPLICATION  DEVELOPER's GUIDE ).
 There is a nice solution in Oracle 8.x -  using INSTEAD OF trigger on VIEW during the update.  In Oracle 7.x - you must use temp. table / PL/SQL tables  and AFTER STATEMENT triggers to bypass it.

 HTH. Michael.

In article <Pine.LNX.4.10.9910071343130.4122- 100000_at_ace.ulyssis.student.kuleuven.ac.be>,   Wim Derweduwe <kalimero_at_ace.ulyssis.student.kuleuven.ac.be> wrote:
>
>
> We have a table with a key1, key2, figure1, calcul1 fields.
>
> What I want to do is an update trigger that when a row is updated or
a new
> one is inserted that it calculates the calculated field calcul1
dpending
> on other row in that table.
>
> But what happens? As the lines is updated oracle starts the trigger
and
> updates the calculated field, so the row is again updated and it
starts
> again the trigger or is that a wrong consumption?
>
> Wim
>
>

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Before you buy. Received on Thu Oct 07 1999 - 15:39:06 CDT