In the above video we have Sean McKenna from the Windows Phone Platform talking about SQL Compact, a new, less sexy but essential feature for developers in Windows Phone 7.
Of note is that SQL Compact was a feature that was cut in Windows Phone 7 to ensure the software came to market on time last year, but that Microsoft always intended to bring it back.
Scott also addressed when developers should be using SQL Compact, and notes for small collections of data the feature is redundant and may in fact reduce performance.
The size of databases are limited to 512 MB in WP7.5, which should be enough for anyone.
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