> > BTW I would not recommend "SET CLIENT_ENCODING TO 'BIG5'" to do an
> > on-the-fly encoding changes. Since in this way, frontend side has no
> > idea what the client encoding is. 7.0.x overcome this problem by
> > introducing new \encoding command. For 6.5 or before I would recommend
> > to use PGCLIENTENCODING environment variable.
>
> You are right! When I do \encoding BIG5, it works.
> But it seems that "\encoding" can only be issued in
> psql's command prompt or be done with
> PQsetClientEncoding() in libpq.
Yes.
> If our application for input is written in PHP (4.0.2)
> How do we notify PostgreSQL that the frontend encoding
> is 'BIG5' ? (pg_exec("\encoding BIG5") failed.)
I know there are some patches for supporting \encoding in PHP. Do you
want to get them?
> PostgreSQL 7.1 will support automatic code conversion for
> BIG5 to utf-8. Does it means that we do not have to
> announce client encoding as long as the backend is utf-8?
No. You still need to declare that frontend side encoding is BIG5.
> I have also tried to set the environment variable
> PGCLIENTENCODING to 'BIG5'. But when I execute
> psql and then issue \encoding, it shows 'SQL_ASCII' in 7.0.2.
> Is this environment variable useless in 7.0.x and latter?
After checking the souce, I found the capability to recognize the
PGCLIENTENCODING environment variable has been broken since 7.0.
Attached is the patches for 7.0.3. I am going to fix current as well.