Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> > PostgreSQL suppots SJIS, BIG5, GBK, UHC and GB18030 as client encodings,
> > but we cannot use them as server encodings. Are there any reason for it?
>
> Very much so --- they aren't safe ASCII-supersets, and thus for example
> the parser will fail on them. Backend encodings must have the property
> that all bytes of a multibyte character are >= 128.
But then, PG_JOHAB have already infringed it. Please see johab_to_utf8.map.
Trailing bytes of JOHAB can be less than 128.
It's true that other server-supported encodings use only characters >= 128.
Regards,
---
ITAGAKI Takahiro
NTT Open Source Software Center