It probably means that in any row for any varchar2 column you can only have
4000 bytes. You can still have multiple varchar2 columns. Depends upon how
often the row gets that large. If most of the time it is 200 bytes and
occasionally 4000 then varchar2. Also if the row grows or changes due to
updates then varchar2 is less of an option. If it is static then varchar2 is
okay.
Jim
"Zeyad S" <sweidanz_at_yahoo.com> wrote in message
news:3B04D944.9056F4B5_at_yahoo.com...
> Jim Kennedy wrote:
>
> > You can only fit 4000 bytes in a varchar2 column. You may have multiple
> > varchar2 columns each with 4000 bytes. That said, if you have a
database
> > block size of 8K and you have 4 varchar2 fields and each has 4000 bytes
of
> > data then you will cause chaining (since it can't all fit in on database
> > block). Your application won't have to do anything special to get the
data;
> > it just means the server works harder doing multiple IO's for that row.
If
> > you need a very large character column then I would use a CLOB. It can
> > store the data out of line so you don't get chaining. It depends upon
your
> > needs.
> >
> > Jim
>
> Thanks Jim, but what does '4000 bytes per row' means? I am just trying to
> understand why Oracle said that while we can create more than 4000 bytes
per
> row?
> Also, when do consider a character column to be very large and consider
using
> CLOB?
>
>
> thanks,
> Zeyad
>
>
>
> >
> >
> > --
> > Our new email address is kennedy-family_at_home.com
> > .
> > "Zeyad S" <sweidanz_at_yahoo.com> wrote in message
> > news:3B0370B6.36993F3C_at_yahoo.com...
> > > Folks,
> > > In Oracle documentation, specifically Application Developer's Guide,
> > > they mention the following:
> > >
> > > Varchar2(size) Variable for each row, up to 4000 bytes per row.
consider
> > > the character ser(one-byte or multibyte) before setting size.
> > >
> > > My question is: is the 4000 bytes is really the maximum bytes per row
or
> > > there is something misleading here? I tried it and create a table with
> > > more than two fields one with varchar2(4000) and the other with
> > > varchar2(200) without any problem. Also i inserted two records and
> > > retieved them without any problem.
> > >
> > > Am I missunderstanding something here? and when should i consider
using
> > > CLOB datatypes?
> > >
> > > Thanks,
> > > Zeyad
> > >
> > >
> > >
>
Received on Fri May 18 2001 - 08:44:43 CDT
