Coding for Multiple Databases in C/C++?

scorp1us asks: "I'm working on a project which was coded in C/C++ to use a MySQL database. I've since been ordered to make it work with other databases as well. I found one that was close to what I want, SQLAPI++, but it is not database agnostic. You end up using the same function calls but you also end up having SQL for each database. I'm looking for a product that looks like DirectX, but for databases (DirectX emulates features in software if no hardware acceleration is present.) PHP's ADOdb is what I want, but I need it in C/C++. Has anyone seen something like this? My last requirment that it must work for MySQL, MS SQL server, and Informix, and work under Win32 and Linux."