As @szeiger points out `Prepared` does not exactly capture what is happening underneath, as we always use prepared statements. On the other hand it may match the use case users have in mind. `Prepared` along the lines of "optimize as far as you can with the information you already have right now". I think `Prepared` is much clearer than `Cached` and if we put a comment about the relationship to prepared statements into the docs I am fine. `Compiled` may be even clearer though :).