Hi
Foxpro is one I haven't used. Have used DB2, Dataquery, Oracle, SQL Server and even had to use IMS.
Access has too many things that are non standard, and seems to have an obsession with pointless brackets when doing joins. Also won't allow you to use constants in an ON clause when doing outer joins.
And its dates are a complete nightmare as it seems to randomly decide whether you mean ddmmyyy or mmddyyyy.
All the best
Keith