On Mar 6, 3:17 pm, "Terry Dykstra" <tddyks..._at_forestoil.ca> wrote:
> "Maxim Demenko" <mdeme..._at_gmail.com> wrote in message
>
> news:45ED2914.6020304_at_gmail.com...
>
>
>
> > vanna..._at_gmail.com schrieb:
> >> Hi all
>
> >> What's the difference between the case and decode functions in oracle.
>
> >> Thanks in advance.
>
> > The short answer - there is practically no difference.
> > The slightly longer one:
> > 1) CASE is ANSI compliant, decode is proprietary
> > 2) CASE is longer to write, but easier to read - with decode you write
> > very compact
> > 3) They have different behaviour by handling NULL's - so the same logic
> > coded with decode and case yield different results
>
> > SQL> with t as (
> > 2 select 1 id,2 id2,null val from dual)
> > 3 select decode(val,null,id,id2) decode_val,
> > 4 case val when null then id else id2 end case_val
> > 5 from t
> > 6 /
>
> > DECODE_VAL CASE_VAL
> > ---------- ----------
> > 1 2
>
> > Best regards
>
> > Maxim
>
> CASE can handle complex expressions that DECODE cannot.
>
> --
> Terry Dykstra
Exactly, DECODE is very similar to "simple" CASE, but very different
to "searched" CASE.
Received on Tue Mar 06 2007 - 17:50:15 CST
