Re: getting NCHAR data into our database

Yes it is variable width. It appears (according to the docs) that when dealing with a variable width character set, Oracle uses another code path that does not perform as well. They don't quantify the amount of performance degradation though. On the application side (at least with Java) ,it is all converted to Unicode anyway so I don't think it will cause any performance impact there.(?) I plan to do performance tests to try to determine the performance impact.

   Where are all the experts on this stuff? Do they not participate in newsgroups or are there just no experts? Enquiring minds want to know:>

    Adam

"tiny anklet bells" <nroshak_at_hcs.harvard.edu> wrote in message news:8a6ccg$5ro$2_at_news.fas.harvard.edu...
> I do believe UTF8 is variable-width. For performance in some
> applications, a fixed-width character set may be preferable. as far as i
> can tell, that's the reason to use anything else...
>
> .n.
>
> Zorg Adam hath momely rade gribble:
> : I am going through the same exact exercise. It appears that the
 national
> : character set has to be a subset of the database character set(?). If
 this
> : is true, then maybe the database character set should be UTF8 and the
> : National Character set should ASCII. Anyway, to insert data, you can
 do
> : this: insert into foo values (n'ascii to be stored in an UTF8
> : olumn'); --Note the "n".\
 

> : I too would like to hear :
> : 1. Is anyone doing this.
> : 2. Is there a reason to? Considering it is possible to create a
 database
> : with UTF8 and never store a multi-byte language (and thus not having a
> : storage consideration), is there a performance impact for doing so. If
 not,
> : why wouldn't you always build an UTF8 database so that it would be
 easier to
> : support foreign languages in the future?
> : 3. Do I have to use the nls_charset library with JDBC to use the
 nvarchar2
> : datatype?
 

> : I hope this helps you. I would be happy to exchange information on
> : this...Thanks
 

> : "tiny anklet bells" <nroshak_at_hcs.harvard.edu> wrote in message
> : news:89mfp2$bei$2_at_news.fas.harvard.edu...
> :> Is anyone out there running a database that stores NCHAR data in a
> :> different character set than the overall character set? If so, please
> :> help me out here.
> :>
> :> Recently we decided that our testing database needed to store NCHAR and
> :> NVARCHAR data in a UTF8 national character set. The database was built
> :> with US7ASCII character set. I did ALTER DATABASE SET NATIONAL
> :> CHARACTERSET "UTF8" (etc), and the data is being stored and read
> :> correctly.
> :>
> :> The question is: How do you get fresh NCHAR data into the database
 when
> :> the character set != the national character set? The Oracle NLS
> :> documentation says, "Because SQL text such as the literals in SQL
> :> statements can only be represented by the database character set, and
 not
> :> the NCHAR character set, you should choose an NCHAR character set that
> :> either has an equivalent or subset character repertoire of the database
> :> character set." That is, we cannot input UTF8 literals into the
 database
> :> (either through SQL*Plus or through SQL statements passed by the
> :> application we're testing).
> :>
> :> Now I -know- there must be people out there who use a different
 NATIONAL
> :> CHARACTER SET than their CHARACTER SET -- otherwise what's the point of
> :> having NCHAR data at all? So there -must- be a way to get fresh NCHAR
> :> data into our tables. The question is, how the heck do you do it???
> :>
> :> At the moment, the only solution we've come up with is to put the UTF
 data
> :> into a flat file and import it using SQL*Loader. Yuck, yuck, uuugly.
> :> Please, post and let me know what the "standard" way is, or how you've
> :> been doing it.
> :>
> :> TIA,
> :> Natalka Roshak
> :> --
> :> He stands proud in his uniform
> :> He knows he's made it now
> :> He's been told he'll be a hero
> :> But he hasn't been told how
> :> He receives his plastic key to heaven
> :> Takes his holy vow
> :> Then he turns,
> :> Then he's gone
> :> --Peter Ulrich, "Taqaharu's Leaving"
>
>
>
> --
> He stands proud in his uniform
> He knows he's made it now
> He's been told he'll be a hero
> But he hasn't been told how
> He receives his plastic key to heaven
> Takes his holy vow
> Then he turns,
> Then he's gone
> --Peter Ulrich, "Taqaharu's Leaving"
Received on Thu Mar 09 2000 - 00:00:00 CST