JR,
>If you're in the habit of using parameterized queries rather than scans or seeks against large tables, conversion to some other platform is easier. In our case, we've used C/S backends and parameterized queries since 1995. Any of that stuff can be ported anywhere.
Keep your eye on the evolution of SQL Server CE (Compact Edition) -- a product that has had more name changes than you can imagine. It was recently referred to as Mobile Edition and also as SQL Server Everywhere. The March issue of Visual Studio Magazine has a pretty good introductory article about it ("Lighten Up Your Local Databases").
During several of the Orcas presentations last week, SSCE was being used as a "caching" layer, very much like we might use an updatable view or cursor, with LINQ talking to that layer and processing updates against it. There was a Synchronization mechanism that was called in the samples to send the updates on to the permanent backend, although the SSCE *can* be used as a standalone database.
It was interesting to see a reference in the article to the SqlCeCommand CommandType.TableDirect property, which can let you use the high-speed SqlCeDataReader's Seek method on indexed columns to position the record pointer. Sound familiar? However, the article writer couldn't figure out how to use the Seek because there was little documentation for it yet in Books Online. I'm guessing that it might not be so hard to figure out. :-)
I haven't had time yet to look closely at SSCE to assess just what it is capable of (particularly in persisting data to disk and/or the spanning issue you refer to), but I suggest you keep your eye on it when investigating .NET's data-handling evolution related to LINQ.
The current version of SSCE probably doesn't include all the features we saw in demos -- there MAY be a newer version in the March Visual Studio Orcas CTP download, but I'm not sure about that. I haven't had the time yet to download and install the CTP.
Anyway, I got a chuckle from the reference to Seek and Record Pointer. :-)
