Valentina Server includes two database servers (Valentina DB and SQLite) as well as a powerful Reports Server. Paradigma Software has a special version we call Valentina Server Free, which like the name suggests, can be used by certain individuals and organizations without any cost.
We've been updating our 5.x documentation to 6.x and just finished updating our frequently asked questions about Valentina Server Free. Go ahead and check it out.
Also, feel free to ask questions in reply to this one in regards to Valentina Server Free licensing. We will update the FAQ as we answer questions.