> I have a very large MS Access Database system (lots of tables that aren't too big) broken into multiple front end and backend MDBs.

That does seem to be the only way to get Access to work.

> Eventually Access is not going to perform satisfactorily so I need to upsize.

My customers were having problems after only 18 months,
50-60 second responce time on some actions.

> I only want to maintain one front end system (Access or VB probably) which can attach to two backend systems: 1. Access MDBs (they work great for our smaller clients) and 2. Firebird (or some other SQL server)

We just moved those applications over to IBObjects and the
customers are more than happy with the results.

> Is this realistic? Should I be looking at another SQL server (MS SQL, PostgreSQL etc)? Does the ODBC driver perform well with Access/VB? Any thoughts on this would be appreciated.

Personally I can see no point in complicating things more
than necessary, but then I am lucky in that my customers are
not entrenched in other systems and can change. Using
several interfaces between user and data will always be
slower than direct access, and I think that the problem with
Access is at the user end, so just replacing the backend my
not make much difference. But I stand to be corrected there
<g>

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Lester Caine
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L.S.Caine Electronic Services