The primary key should not be prefetched if an composite primary key is used. I adjusted the prefetch condition to support this.
Do not pre-fetch the primary key if multiple primary keys exist
thank you @andfx ... would it be too much to ask for a test :) ?
Verify that the primary is prefetched when needed
Thanks for the response @kares ... I added the tests.
commits are on master a4b1770 and d69ad99 I've added this for FB as well abe8b92 ... thanks again!