Have you considered populating the SQL Mobile database on the desktop from
the DBF data and then just using that file on the device? Although I tend to
agree with Cindy that searching through 10,000 items in a datagrid might not
be practical, searching through that many records in a SQL Mobile database
can be quite fast depending on how you do it. In fact, if you bind a
SqlCeResultset to a DataGrid, even if you have 10,000 records, you only take
an initial hit for the number of records that are represented by visible
rows. Combined with a way for the user to tell you what he's interested in
so you can refine the SqlCeResultSet, this could give you very good
performance.
The sticking point at the moment is how to create the sdf file on the
desktop side. You can see from this article posted today that there will be
a new version of SQL Server Everywhere Edition that will run on mobile and
desktop devices, and best of all for SQL Mobile users you don't need to
learn any new technology. That means that work can begin immediately on
prototyping for this new version of SQL Server, although it can't be used
for production until release - planned for the end of the year. Here's the
link:
http://www.microsoft.com/sql/letter.mspx
Here's a blog discussing using SQL Mobile on the desktop:
http://blogs.msdn.com/smartclientdata/archive/2005/07/15/439008.aspx