A very well known SQL database
The driver pgsql is a 100% erlang implementation of the Postgres FE/BE protocol.
Early development was committed to jungerl. This is the exact same codebase, except I now use GIT and host the project at github.
The driver has been used by many people, but still needs to mature.
Christian Sunesson (me). Over the years I have received about one or two suggestions (thanks!). But all the code is written by me.
It was my first real Erlang project, and thus it is not an OTP application, nor is it very apt at being concurrent.
Find pgsql at github.
None.
The Erlang Public License, its similar to the Mozilla public license in terms. You should find it and read it if you're worried about these things.