- File (.dat, .dbf, .xls, .csv) = Car, Motorcycle, walking
- SAM (.mdb (Access), MSDE = Van or large 4 wheeled truck
- SQL (MS SQL) = a fleet of semi-trucks nearing trains
- Oracle = a fleet of trains nearing 747’s
- DB2 (mainframe) = a fleet of trains, 747 airplanes and very large/fast cargo ships
So you use the database vendor for the need, size, cost and ease.