Re: dipendence between NLS_CHARACTERSET and NLS_NCHAR_CHARACTERSET parameters

Cris Carampa <cris119_at_operamail.com> wrote in message news:<bdeh0l$50o$1_at_panco.nettuno.it>...
> I created my database (Oracle 9.0.1.3 on SuSE SLES7) with
> NLS_CHARACTERSET=US7ASCII and NLS_NCHAR_CHARACTERSET=AL16UTF16 because
> my intention was to use NVARCHAR2 columns for storing multilanguage strings.
>
> I thought these two parameters were independent from each other. But
> then I came into "bug" 2858947 (actually, not a bug but an expected
> behaviour):
>
> "When a string literal is included in a query and the query is submitted
> through a client-side tool such as SQL*Plus, all the queries are encoded
> in the client's character set and then converted to the server's
> database character set before processing. Therefore, data loss can occur
> if the string literal cannot be converted to the server database
> character set."
>
> This make NVARCHAR2 columns absolutely usable for me. But, as I
> understood correctly the above paragraph, even if my database were
> created with WE8ISO8859P1 charset I would not have been able to store
> anything but WE8IS8859P1 strings in NVARCHAR2 columns, because all
> string literals would have been "converted to the server's database
> character set before processing". So what is the aim of NVARCHAR2
> datatype? I'm confused.
>
> Kind regards,

No. Basically it says: if your database character set and your client characterset do not match, ie the database character set is a subset of the client, you will get conversion.
Is your AL16UTF16 a subset of WE8ISO8859P1. Don't think so. If however your client doesn't support this characterset, you won't be able to store AL16UTF16 characters in the database.

Regards

Sybrand Bakker
Senior Oracle DBA Received on Thu Jun 26 2003 - 07:55:07 CDT