100K records is a lot to do anything to in compact edition; it's mostly up to the processor and indexing. are you just searching in compact edition? what exactly are you doing with 100K of records? do you have a table structure yet?
your title states "retrieve 100K records". that is going to be slow, no matter what. none of my portable devices could display 100K records without being dog slow; you'd be much better off paging record groups and displaying in batches, if that is what you are doing.
you are using SQLite instead of SQL Server Compact Edition database?
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