RE: [DebianGIS] postgis trouble

["F.Sluiter" <fsluiter@gmail.com>]

Hi Paolo,

There are several approaches to this problem (I ran into the same
while upgrading).

First: your database will work, it just cannot find the proper postgis library.
What happened is that postgresql7.5 just changed the paths of most of
the binaries, but none of them are replaced (it is still postgresql
7.4).
It did not copy the postgis library to the correct path, so you have
to do that manually.
cp /usr/lib/postgresql/lib/libpostgis* /usr/lib/postgresql/7.4/lib/

now postgresql can start and find your libraries again.
/etc/init.d postgresql start

If you do want to upgrade from postgresql 7.4 to 8.0 I strongly
recommend installing postgresql-common and study its setup (it allows
multiple concurrent versions of postgresql/postgis).
documentation is then in "man pg_ctlcluster" and on:
http://people.debian.org/~mpitt/postgresql-ng.html

Now, you can (manually) dump the original tables SEPARATELY (not the
whole database!) and upload them in the new server. Do follow the
guidelines in the postgis documentation and DO NOT attempt this
automatically with scripts etc. I did, and it didn't work (yet). The
new postgis packages might solve this in the future, but you should
not use it in a production environment yet.
The main thing is that some of the datatypes and functions changed, so
the libraries are not binary compatible and the functionlist/datatypes
will not migrate properly.

Hopefully Alex (with a little help from us) can solve this
updating/migrating very soon...

Let me know if you need more help!
 Succes!

Floris