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Re: How are unlimited fields stored?

From: stu <smcgouga_at_nospam.co.uk>
Date: Thu, 24 Oct 2002 09:16:51 +0100
Message-ID: <ap8aai$qb2$1$8302bc10@news.demon.co.uk>


So to stop fragmentation when updating varchar(xx) fields the dbms must store the varchar(xx) fields in a separate structure from the constant length fields?

cheers
Stu

"Lennart Jonsson" <lennart_at_kommunicera.umea.se> wrote in message news:6dae7e65.0210230817.664570b9_at_posting.google.com...
> "stu" <smcgouga_at_nospam.co.uk> wrote in message
news:<ap5mue$s7m$1$8300dec7_at_news.demon.co.uk>...
> > How are large unlimited fields stored? I think im right when i say if
you
> > have a TEXT(30) and only use 3 chars the dbms will physically layout 30
char
> > space before the start of the next record. This is fine but how does
the
> > dbms handle memo fields that can be huge?
> >
> > Cheers
> > Stu
>
> I seem to remember that text and memo are part of access (which I dont
> have). Anyhow, normally there are text fields that allow varying
> length as well. For example varchar(xx). The principle is that the
> length of the data is kept together
> with the data. Thus the db nows how long the data actually is. The
> overhead is of course the extra bytes that is needed to remember the
> size.
>
>
> HTH
> /Lennart
Received on Thu Oct 24 2002 - 03:16:51 CDT

Original text of this message

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