To start with prelude, you have to install at least one DBMS module for
libpreludedb, e.g. prelude-libpreludedb-pgsql .

Then, install the database. Here is the instructions for PotsgreSQL:

# su - _postgresql
$ createuser --pwprompt prelude (default password "prelude" / n,n,n)
$ createdb -O prelude prelude
$ cd /usr/local/share/libpreludedb/classic/
$ psql -U prelude -W prelude < pgsql.sql
