Re: VARCHAR2(1) vs CHAR(1)

The main difference between char and varchar is that char stores trailing spaces, while varchar does not store it. This mean that if you insert 'UGO' in a char(6) field, the result is 'UGO___' with 3 spaces at end; if you do the same in a varchar one, the result is 'UGO' with no spaces at end.
With varchar type trailing spaces are removed. For a varchar(1) you shouldn't have any problem; it holds only one character. All applications should work fine.
Consider only one case: if you insert a space in the field. The field now contains ' ', but isn't null.

Hope I help you,
Marco

"Stjepan Brbot" <stjepan.brbot_at_zg.hinet.hr> ha scritto nel messaggio news:ai1p0f$fer6$1_at_as201.hinet.hr...
> If I change VARCHAR2(1) into CHAR(1) column type in table, what could
> happened? Will the application (expecting the VARCHAR2(1) column type)
> work correctly anymore by automatically converting the value from
> CHAR(1) into VARCHAR2(1) type?
>
> --
>
> Stjepan Brbot
>
>
> "Marco Muracchioli" <reply.on_at_group.please> wrote in message
> news:aqP09.129764$Jj7.2997288_at_news1.tin.it...
> > Hi,
> >
> > you should use char type if you need to store 1 or 2 char in the
> field.
> > Consider that varchar types need, phisically, more information than a
> simple
> > char type (such as size).
> > If you know that the field always contains null or 1 character (null
> or 2
> > characters for char(2)), char is the cheapest and fast solution.
> > "Fast" include the more speed than the DBMS need to organize and
> manage a char
> > data, because it always know the exact size and never need to
> calculate it.
> >
> > Marco
> >
> >
>
Received on Sun Jul 28 2002 - 17:07:10 CDT