Excel as frontent and XML file as database? Multiuser capable?

Hello everybody,

I'm faced with a problem that I cannot find a solution that suits me. I must start soon a new project that will use Excel 2007 as the user interface. This application must manipulate Excel data (reading, modifying, deleting). For technical constraints imposed by the client, I cannot use SQL databases like SQL SERVER nor ORACLE nor ACCESS, ... Eventually XML files do the trick since it does not handle large amounts of data but the problem is that this application should be multi-user (4 or 5 people). I think XML files (flat files) do not work in multi user environment, isn't? It will certainly happen that several users try to access the same data (tables) at the same time and here I do not think that with the XML I can get out easily.

One of you have an idea to submit to me? I searched a lot without success.

So the constraints are:
- Frontend must be Microsoft Excel 2007
- No DB like SQL Server, Oracle, Access
- Multi User (4 or 5 people)
- Not much data to handle (a few hundred records on a few tables)
- No referential integrity to manage

Thank you in advance for your help!

Originally Posted by royUK

Excel is not reliable with multi-users

I know. I intend to use Excel as a frontend only and use something else to manage my data. I think an XML file is not a good choice for the backend in a multi user environment. I think about using a jet database (mdb file) but I need advises.

Originally Posted by shg

The front end is where the multi-user part would be happening, right?

That's an Access database, which I thought you said you couldn't use.

You are right. I am afraid that my client will not accept an 'mdb' solution. But I try to enumerate all solutions.

(1) an xml file
(2) a jet (=Access) mdb file
(3) Sql Express
(4) Sql Compact

The critical point is the multiuser capabilities. I know that points (2) (3) (4) allows multiuser.
What about point (1) ? An XML file is in fact a flat file and I wonder if it can support multiuser (for 4 or 5 people)???