Re: invalid UTF-8 byte sequence detected

Hi!

> -----Ursprüngliche Nachricht-----
> Von: Bruce Momjian [mailto:pgman@candle.pha.pa.us]
> Gesendet: Dienstag, 15. November 2005 19:46
> An: Markus Wollny
> Cc: pgsql-general@postgresql.org
> Betreff: Re: [GENERAL] invalid UTF-8 byte sequence detected
>
>
> I am also confused how invalid UTF8 sequences got into your database.
> It shouldn't have been possible.
>

Our databases were originally encoded in ASCII, though they should have been LATIN9 - or UNICODE; this has been
remedieda long time ago using iconv on the dumps; our PostgreSQL-version then was 7.4 and we converted databases and
dumpsto UTF-8. Maybe the invalid byte sequences have been entered sometimes during our migration from ODBC to JDBC
whileour encoding was still a mess - though I would have thought that this should have been resolved by
dump&iconv&restorethen. However, I do suspect that the cause of the issue was really more or less a bug in PostgreSQL
<8.1,which accepted certain illegal byte sequences. I our case, I found that the re-import of the dump errored out on
ISO-8859-1encoded backticks (´) - certain mournfully misled individuals do use this "degu"-character instead of the
apostropheeven tough it's more difficult to type on a german keyboard layout. And quite wrong, too. 

Anyway, I found some reference in the hackers-list that encoding-consistency for Unicode has been tightened down (see
http://archives.postgresql.org/pgsql-hackers/2005-10/msg00972.php). Both a solution and a suggestion have been posted
inthis thread; Christopher Kings-Lynne has suggested to include a reference to this issue in the 'upgrading/back
compatibiliy'section for these release notes - I do strongly second his suggestion :) 

The suggested solution was to feed the plain dump again through iconv; however at least on my systems (Debian Sarge)
iconvdidn't like my >5GB sized dump files. So in order to successfully reimport the dumps, I had to "split
--line-bytes=650m"the SQL-file, pass the parts through iconv -c -f UTF8 -t UTF8 and concatenate them back into one file
again.There were no more errors on feeding the dump back into psql and I didn't come across any missing data during my
tests,so this has definitely done the trick for me. 

As 8.1 has tightened down encoding-consistency for Unicode, I believe that the databases should be safe from any
illegalbyte-sequences in text-fields from now on.  

Kind regards

   Markus