>What is the difference between including and excluding a dbf into a database.
>Thanks.

A database or project Cemal ?
Database : It's a kind of data dictionary.
You get extensions like long fieldnames, caption, defaultvalue, triggers, persistent relations, referential integrity, stored procedures etc
Also it'd be easier for you to talk via ODBC, OLEDB (possible with free tables too but slightly harder).
In future version(s) new database events are also upcoming.
IMHO if you don't have a good reason not to do so add them to a database.
Project : Basically if included readonly.
Cetin