Database engine advice.
I noticed that CityDesk uses the JET database engine.
I can't speak for Fog Creek on the reason for the choice, but can point out one thing: if you have Access, you can install the Access-SQL Migration Wizard and migrate the CityDesk tables to a SQL Server database. The JET file will be retained, but all requests will be processed against the SQL database.
These are the things we like best about Access:
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