Re: Performance and datatypes

From: Ulrik Hoffmann <ulrik_at_hoffmann-kiel.de>
Date: Mon, 26 Jul 1999 22:26:33 +0100
Message-ID: <7nigav$35s$1@freeside.cls.net>

Hi Skip,

the char datatype is always using the space you specify:

Char(30) needs 30 Bytes for each row. If you have a smaller column-value, the rest is filled with spaces (or maybe I'm wrong, but I never use char!).

Varchar2(30) just needs the bytes the value needed or one or two bytes for null values.

So one performance reason is, that an index on a char column will be bigger and slower than a varchar2 index.

Bye
Uli

<skips_at_my-deja.com> schrieb in im Newsbeitrag: 7nifiu$tv7$1_at_nnrp1.deja.com...
> Are there any ramifications for using the varchar datatype with regards
> to performance, as opposed
> to using the char datatype?
>
> I with other databases this can be an issue but I have not been able to
> find any documentation on Oracle that relates to this subject.
>
> Thanks
>
> Skip
>
>
> Sent via Deja.com http://www.deja.com/
> Share what you know. Learn what you don't.
Received on Mon Jul 26 1999 - 16:26:33 CDT