Can PostGreSQL handle 100 user database?

I plan to convert a Foxpro system to client/server - hopefully using PostGreSQL
(about 100 tables / 300 mb / 100 users)

Firstly I heard a rumour that p-sql doesn't process queries in parellel, i.e.
performs them sequentially.
Is this true? If so it would surely make it impracticle when more than a few
clients are connected
I tried this out by running 2 VB programs via ODBC than randomly performed
queries - they appeared to work
in parallel - however I then started a PSQL session and entered a slow query it
appeared to stop the 2 VB programs until
it had completed. Anyone got the answer to this???

The other question I have is how much memory I should really have to support 100
connected clients. There must be a formula / rule of thumb for this?

I am hoping I can convince my customer to use postgresql but first I need to
convince myself it is up to the job :)
I am actually pretty impressed with it so far, its got a lot of functionality
that DB2 doesn't have

Thanks,

M Chantler
Southampton

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