Database design for database-agnostic applications

Question

What do I have to consider in database design for a new application which should be able to support the most common relational database systems (SQL Server, MyS

Answer 1

If at all possible I would avoid doing this. I have worked with several of these databases in the past and they were horribly slow (one particularly painful example I can think of was a call center application that took ten minutes to move from one screen to another on a busy day) due to the need to write generic sql and not use the performance tuning that was best for the particular backend.