>> > Shouldn't this be done only for NATIONAL CHAR?
>> It is what USE_LOCALE is intended for, isn't it?
LOCALE is not very usefull for multi-byte speakers.
>SQL92 defines NATIONAL CHAR/VARCHAR as the data type to support implicit
>local character sets. The usual CHAR/VARCHAR would use the default
>SQL_TEXT character set. I suppose we could extend it to include NATIONAL
>TEXT also...
>
>Additionally, SQL92 allows one to specify an explicit character set and
>an explicit collating sequence. The standard is not explicit on how one
>actually makes these known to the database, but Postgres should be well
>suited to accomplishing this.
>
>Anyway, I'm not certain how common and wide-spread the NATIONAL CHAR
>usage is. Would users with installations having non-English data find
>using NCHAR/NATIONAL CHAR/NATIONAL CHARACTER an inconvenience? Or would
>most non-English installations find this better and more solid??
The capability to specify implicit character sets for CHAR (that's
what MB does) looks enough for multi-byte speakers except the
collation sequences.
One question to the SQL92's NCHAR is how one can specify several
charcter sets at one time. As you might know Japanese, Chineses,
Korean uses multiple charcter sets. For example, EUC_JP, a widly used
Japanese encoding system on Unix, includes 4 character sets: ASCII,
JISX0201, JISX0208 and JISX0212.
>At the moment we have support for Russian and Japanese character sets,
>and these would need the maintainers to agree to changes.
Additionally we have support for Chinese, Korean. Moreover if the mule
internal code or unicode is prefered for the internal encoding system,
one could use almost any language in the world:-)
>btw, if we do implement NATIONAL CHARACTER I would like to do so by
>having it fit in with the full SQL92 character sets and collating
>sequences capabilities. Then one could specify what NATIONAL CHAR means
>for an installation or perhaps at run time without having to
>recompile...
Collating sequences look very usesful.
Also it would be nice if we could specify default character sets when
creating a database, table or fields.
--
Tatsuo Ishii
t-ishii@sra.co.jp