"...For simultaneous user support, there is no
comparison between Access and MySQL. Access begins to short out at
about 15 simultaneous connections, and we've heard complaints when
the number is as low as 5. This is not to suggest that only 5 users
can connect to an Access-supported site at the same time.
Simultaneous connection actually refers to concurrent processes. As
such, Access can actually handle unlimited connections, as long as
those connections remain under the process limit. Read-only sites
(which really aren't as rare as you might think) can support up to
255 users. Larger sites do inevitably upgrade to SQL Server to
improve performance and stability.
In contrast, MySQL's maximum connection default is 100 users.
And while one should never base performance evaluations on a
program's default settings, we haven't heard any complaints from
users relying on MySQL for large sites with heavy connection play.
In addition, plenty of traffic doesn't seem to impact query
optimization significantly.
In tests with equivalent hardware and file sizes on a Windows 98
system, MySQL consistently performs faster than Access 2000--but
not always. Updates show the largest discrepancy in the area of
performance, with Access often requiring twice as long to complete
the same task. When you're dealing with small amounts of data and
fast systems, this discrepancy isn't noticeable. It becomes a
problem only when handling hundreds of thousands of records. MySQL
loses to Access only when dealing with object structure rather than
data. When creating a table and an index, MySQL locks out the
table, which slows things down when working with large amounts of
data. This latter issue isn't really a typical concern in Web
programming, though, where hits and querying matter more than data
storage. In this area, MySQL wins."
