I don't expect that this site will have to handle much traffic so I assume that a standard Raspberry Pi will fit my needs.

Operating System

How do you setup a basic working environment?

sudo passwd root
#Root
adduser username
apt-get install mlocate
#user
chsh -s /bin/bash
sudo apt-get install apache2
sudo apt-get install php5
sudo apt-get install php5-mysql
sudo apt-get install lynx
sudo apt-get install nginx

MySQL/MariaDB

How do you setup the DBMS?

My first intention was to use MariaDB. I have the impression that Oracle is trying to move MySQL out of the Open source domain. And I don't like that. That's why I started with MariaDB.

On my Raspberry, MariaDb was installed with the following commands:
wget "https://downloads.mariadb.org/interstitial/mariadb-5.5.34/kvm-tarbake-jaunty-x86/mariadb-5.5.34.tar.gz/from/http://download.nus.edu.sg/mirror/mariadb" tar -xvf mariadb
mv mariadb-5.5.34 maria
cd maria/BUILD
./autorun.sh
cd ..
./configure
make

It took several hours but MariaDB installed without a glitch.

After that I tried to install

sudo apt-get install mysql-server

SWI-prolog

How do you setup and configure SWI-prolog?

sudo apt-get install swi-prolog
sudo apt-get install swi-prolog-odbc

ODBC

What is needed to set up an ODBC-connection?

ODBC was installed with the following commands (as root):

sudo apt-get install unixodbc unixodbc-dev
sudo apt-get install libmyodbc