So I must say I like Zend’s database layer the best so far. Good abstraction and I was able to build on it. One problem I ran into is when I changed the name of a primary key column (after some architecting). ZF caches the table’s metadata and that meta data is used to build row objects (I am using my custom dto). Because of the cached data things went wrong and I had to  head over to the abstract class  to see why things went wrong.  I have  done my  fair  share of data caching stuff and I am disappointed that as far as I can tell there is no easy way to invalidate the metadatacache (like setting a flag or something), but I am still hoping I just haven’t found it yet