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Thanks.
Regards
Lee
Matthew Fuller <matthewlf_at_my-deja.com> wrote in message
news:9425fi$4p9$1_at_nnrp1.deja.com...
> In article <941ash$nlm$1_at_coco.singnet.com.sg>,
> "Lee" <hengchee.lee_at_aretae.com> wrote:
> > Hi,
> > From the documentation provide by oracle, I 'guess' that every
datatype
> > start with a character has to do with national character set. I
thought
> > that if you gonna to store characters in non-English, for example,
Chinese,
> > Korean, etc., you'll need to use these type.
> > But to my surprise, I manage to store Chinese text in a CLOB field.
(I never
> > tried NCLOB though), and when I create the database, I even just use
the
> > default which is US7ASCII for both Character Set and National
Character Set.
> > So my question is, what good is these type start with n for? And does
your
> > setting in National Character Set affect anything?
> >
> > Thanks and best regards
> > Lee
> >
> >
>
> Lee,
>
> You should not be using the US7ASCII character set if you want to store
> characters that require more than 7 bits of precision (which all
> international character sets do).
>
> It is true that you can store 8-bit data in a database created with
> US7ASCII, but perform this simple exercise to prove why this is bad:
> (1) export one of your tables that has international characters
> (decimal values above 127). (2) make a backup of the table (i.e. CREATE
> <backup_table> as SELECT * FROM <source_table>. (3) DROP the original
> table. (4) Import it from your EXPort file.
>
> You'll notice in the imported version of your table that all characters
> above decimal 127 have now had 128 subtracted from them. This is
> because the 8th bit got stripped. (I've never done the research to
> find out if this is happening in the EXPort, the IMPort, or both).
> Suffice is to say when you use US7ASCII Oracle stores 8 bits of data
> because he doesn't want to go through the pain of storing only 7;
> however he figures you only care about the 7, so he doesn't really care
> what happens to that 8th bit at any point in time.
>
> HTH.
>
> Matt.
>
>
> Sent via Deja.com
> http://www.deja.com/
Received on Tue Jan 16 2001 - 21:32:43 CST