Re: Migrate postgres databases from SQL_ASCII to UNICODE

В Вск, 18.07.2004, в 01:34, Dario V. Fassi пишет:
> Tom Lane wrote:
> > "Dario V. Fassi" <software(at)sistemat(dot)com(dot)ar> writes:
> >
> > > A simple question, we need to migrate many (>20) postgres databases from
> > > SQL_ASCII encoding to UNICODE encoding, over a 7.3.6 server.
> > >
> > SQL_ASCII is not an encoding (it's more like the absence of knowledge
> > about an encoding). What is the data actually stored as?
> >
> > > With Dump/Restore , we get an error (Invalid Unicode) in any field that
> > > has a 8 bits character coming from the SQL_ASCII , even setting the
> > > client_encoding to WIN, ISO-8859-1, and others encodings.
> > >
> > It might work to just UPDATE pg_database to set datencoding to the
> > correct value reflecting what you have actually stored. You might then
> > need to REINDEX any indexes on textual columns, but I don't think
> > anything else would go wrong.
> >
> > If you have a mishmash of different encodings in a single database, then
> > of course there is no simple solution; you are in for some pain while
> > you try to fix the data.
> >
>
> Yes you are right , the original data come from a DB2 with CodePage
> IBM-850 and was inserted without complains in a Postgres 7.3.6 with
> SQL_ASCII.
>
> Now we are in a Jail , because IBM-850 , isn't WIN, isn't ISO-xx ,
> isn't no one postgresql's encoding.
> So when in change via pg_databases the encoding , 8 bits characters
> become garbage.
> More even if we accept this garbage chars and we set encoding to e.g.
> ISO-8859-1 it's impossible go to a UNICODE because this garbage
> chars are invalid in client's encoding , so they are reject (in
> translation process as invalid unicode chars).

You can dump the data, convert it with for example iconv and then load
the data again.

--
Markus Bertheau <twanger(at)bluetwanger(dot)de>