After going through the char* drama we recently went through identifying my database problems, I'm compelled to request that we consider restricting all use of char* to this file. (i.e., have SQLiteBack go back to accepting strings and have this whole HDF5Back class accept strings but convert them to char* when it needs them to be char*). 

For the uninitiated. This change in the api to require char* caused some funky drama that was hard (for me) to diagnose with my Cyder tables. Robert helped a ton and identified the problem, but I think strings might be safer for folks in the long run.