You mention BDE without saying which database system you are using.
In my experience, MySQL performs significantly faster than single user databases such as Access, dBASE and Paradox.
MySQL was designed as a multi user database. Databases such as Access, dBASE and Paradox are essentially single user databases. Paradox, for example, has had a crude locking mechanism added to make it multi user which if I remember correctly locks the whole table which is not efficient if many users are trying to access the table at the same time.
So you will find something like MySQL will be able to handle lots of concurrent users much better than single user database systems.
A multi user database system such as MySQL is much more scaleable than a single user system.
Andrew
Hampshire, UK