> Has anyone ever had any success using either over ODBC? I would expect
> that if a generic "simple sql syntax" adapter were available it would 
> likely
> work on both DBs..

Generic ODBC adapters are problematic because the databases underneath 
might use different strategies for stuff like auto-incremented columns. 
A Access or Sybase adapter that goes through ODBC is certainly 
possible. I know that shashank and a few others were looking into that 
for Active Record at some point.
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David Heinemeier Hansson,
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