Re: PL/SQL: To determine which field was update

From: Chris Hamilton <Christopher.H.Hamilton_at_usace.army.mil>
Date: 1997/08/07
Message-ID: <33E9CAB4.3B04_at_usace.army.mil>#1/1

Benson Butt wrote:
>
> You can do a comparison using :old and :new.
> i.e.
> if :old.fld1 != :new.fld2
> -- do something since the field is updated
> endif

You may wish to use the nvl() function to make sure nulls are compared properly (since null doesn't equal anything, but it doesn't not equal anything either).

For instance,

For varchar2:

if nvl(:old.field1,' ') != nvl(:new.field2,' ') then   blah-blah;
end if;

For numeric:

if nvl(:old.field1,0) != nvl(:new.field2,0) then   blah-blah;
end if;

For date:

if nvl(:old.field1,'01-jan-01') != nvl(:new.field2,'01-jan-01') then   blah-blah;
end if;

Chris

---

Chris Hamilton - Oracle Database Admin.
AVANCO Intl. / US Army Corps of Engineers Christopher.H.Hamilton_at_usace.army.mil http://www.serve.com/cowpb/chamilton.html Received on Thu Aug 07 1997 - 00:00:00 CEST