We use OTL from http://otl.sourceforge.net/ and find it to be very satisfactory. At the time it was the only decent library we could find. I had been curious 
about difficult it would be to use in Ruby (it is a header only- template based library). I don't know if this fits into your design goals though.

6/26/2003 11:36:44 AM, Jim Cain <list / jimcain.us> wrote:

>Michael Neumann wrote:
>> Jim Cain wrote:
>> 
>>> Hi all. I was looking for a Ruby interface to 9i that would handle all 

...snip..


>
>BTW I wrote a similar library for Oracle8 in C++ a few years ago, but I 
>haven't touched that code in a while. It's at http://jimcain.us/orapp/ 
>if anyone is interested.
>
>Cheers,
>Jim
>
>
>