Though i suspect this may be found on the web, you aren't really comparing
apples to apples since the underlying databases are tuned for their
particular environment and optimized accordingly. As an example, in a web
app with less than 40 concurrent users, mysql will beat the pants off of
mssql on any given sunday. But you cannot draw a sweeping conclusion from
that since these datasources are tuned for different environments, one for
high concurrency the other for low concurrency - apples to grapes.
What you should be asking is, given a particular environment y, and a price
cap x with concurrent users n, and processing power p, which is the better
choice.
hth
