> Do any of the encodings with encoding max length > 1 have a constant
> character size (e.g. unicode?). If so, how hard would it be to add
> another member to pg_wchar_tbl, say:
>
> bool mblen_is_const; /* all chars = max bytes this charset */
>
> Then those character sets code gain back much of the same speed
> advantages as single byte character sets when it comes to string processing.
Sounds interesting idea, but none of encodings currently PostgreSQL
supports has fixed length character size. UCS-2/UCS-4 is such an
encoding, we do not support it however.
--
Tatsuo Ishii