I think it depends also on what strengths you already have and how you are personally motivated to learn. For example, I have found java's h2 database to be ea

I think it depends also on what strengths you already have and how you are personally motivated to learn. For example, I have found java's h2 database to be easy to work with (and you never have to leave java). I don't think any db could be easier to get started with and have less administrative overhead than sqlite. If, to learn how to program computer games, one is advised to first write tetris, to learn programming with databases, you might write a message board.