[From SQL Server Magazine
One of the most easily overlooked aspects of the recent SQL Server 2008 release is SQL Server 2008 Express, which is a freely distributable database that shares the same core relational database engine as the full-featured SQL Server 2008 Standard and Enterprise Editions. SQL Server 2008 Express offers full support for the new SQL Server 2008 data types including Date, Time, Hierarchical, Geospatial and FileStream. It doesnt support more enterprise-oriented features like the Resource Governor, Transparent Data Encryption, Integration Services or Analysis Services.
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