Migrating from a version 7.4 to a version 8.2 postgreSQL database, on Debian Etch

1. Compiling and setting up postgres, followin the INSTALL file
   ./configure
   I just ran configure with no customization.
   
   Had to install readline support:
   apt-get install libreadline5-dev

   make (Debian has renamed Gnu make to just make)

   su (if you use su -, you'll need to cd back to the directory where you unpacked the pg source)

   If you don't have a user postgres, add it
   adduser postgres
   I didn't need to add the postgres user since that user allready exists from my previous 7.4 installation

   make install

   Create the folder for the database:
   mkdir /usr/local/pgsql/data && chown postgres /usr/local/pgsql/data

   su - postgres

   /usr/local/pgsql/bin/initdb -D /usr/local/pgsql/data
   After initdb it's probably a good idea to take a backup of the data directory, so that you can just copy in a fresh copy of the db cluster without running initdb if the import fails.

   Make sure your new database works
   /usr/local/pgsql/bin/postgres -D /usr/local/pgsql/data > /usr/local/pgsql/data/logfile 2>&1 &
   /usr/local/pgsql/bin/createdb test
   /usr/local/pgsql/bin/psql test
   Then, stop the postgres instance you started:
   /usr/local/pgsql/bin/pg_ctl stop -D /usr/local/pgsql/data/

   
   
2. Dump the old database cluster:
   /usr/local/pgsql/bin/pg_dumpall -h /var/run/postgresql/ > /tmp/pg74.sql
   It's important to use the version of pg_dumpall from the 8.2 installation.
   
   
3. Stop the old 7.4 postgres database, In my case:
   exit
   /etc/init.d/postgresql-7.4 stop
   su - postgres
   
   
4. Start postgresql 8.2 again:
   /usr/local/pgsql/bin/postgres -D /usr/local/pgsql/data > /usr/local/pgsql/data/logfile 2>&1 &
   
   
5. Now, time to try to import the 7.4 database:
   /usr/local/pgsql/bin/psql -v ON_ERROR_STOP=1 -f /tmp/pg74.sql

   the -v ON_ERROR_STOP makes the import abort if any error is encountered, and using the -f flag to specify the file, instead of using <, makes psql output line numbers from the dump, when outputting error messages.

   This step probably won't work without errors/notices.

6. At this point, this sequence of commands can come in handy:

   /usr/local/pgsql/bin/pg_ctl stop -D /usr/local/pgsql/data/
   exit
   rm -rf /usr/local/pgsql/data/
   cp -r /usr/local/pgsql/data-backup/ /usr/local/pgsql/data
   chown -R postgres.postgres /usr/local/pgsql/data
   su - postgres
   /usr/local/pgsql/bin/postgres -D /usr/local/pgsql/data > /usr/local/pgsql/data/logfile 2>&1 &
   

7. First obstacle are these lines in the dump file:
   CREATE ROLE postgres;
   ALTER ROLE postgres WITH SUPERUSER INHERIT CREATEROLE CREATEDB LOGIN;
   I simply removed them from the dump file.

   I also removed any modifications done to the template-databases.

   I got an error from some of the functions which I had added from old contrib. Since I don't actually use the functions this provides, I simply deleted this from the dump file.
   psql:/tmp/pg74.sql:65031: ERROR: could not access file "$libdir/fuzzystrmatch": No such file or directory

   
   
8. Well... thats it
   2 hours after starting, I'm done