Can CF and ASP Access the Same Database?

Question

Hello. I'm about to go into beta with a ColdFusion 8 site I
just wrote, and I've just realized there could be a problem I
haven't anticipated. There's another site, written in ASP, which
will accessing the same data at the same time. The data are in
FoxPro for DOS, which (if I have the terminology right) is a 'file
server' database. Both my site and the ASP site will be accessing
it through ODBC. I will be accessing it on a read only basis, and I
believe the ASP site accesses it read only as well. However, other
employees in the company are constantly accessing it read/write.
The ASP site has been already up and running for some time,
and the office manager (it's a small company) finds that he is able
to avoid conflicts by first stopping the ASP server each morning,
then starting FoxPro, then re-starting the ASP server. (I do not
mean the IIS server, but a little EXE written by the ASP
programmer, which puts up its own little window with 'start' and
'stop' buttons on it.)
However, I find that on my own PC, using the free Developer
version of ColdFusion and accessing my site as localhost, if a DBF
(database file) is opened in FoxPro (even if no one is currently
writing to it), then my CF web site cannot access it, and vice
versa. That is, if I start FoxPro first and open the DBF of
interest, my web site can't access that DBF. And conversely, if I
access it first via my web site, then FoxPro can't access it. In
other words, the solution which works for the office manager and
his ASP site does not work for me with CF on my local PC.
Will matters be different in their system, where I will be
installing my site tomorrow, along with the Standard version of CF
8? If it matters, the FoxPro data and the Web server will be
different boxes linked by a network. The operating system is
Windows 2003 if I recall correctly.
Should I be saying 'Oops!' right about now?
I can probably come up with a workaround by having FoxPro
write a record to an alternate DBF every time the DBF of interest
to my site is updated, but will I have to do this?
Thanks for your help.

Answer 1

paross1 wrote:
> there probably isn't
> much that can be done with a database that probably
isn't designed for multiple
> simultaneous transactions.
>
> Phil
>
Not much that can be done to make the database robust and
handle
simultaneous transactions. But you could wrap all your CFML
that
accesses this resource in named <cflock ...> tags so
that they are
single threaded, thus restricting CF to one access at at
time. Then
wrap all of this up in a <cftry><cfcatch...>
blocks to gracefully handle
when the database is locked up by some other user/process.
You will still have many times when the CF application will
not be able
to access the resource do to locking issues, but it will
handle this
gracefully and not just FAIL.
Of course this will have serious performance, throughput and
scalability
consequences. But I suspect if you are using something like
FoxPro you
are not building an application expected to handle heavy
load.