MSDE

Microsoft SQL Server Data Engine (MSDE, also Microsoft Data Engine or Microsoft Desktop Engine) is a relational database management system developed by Microsoft. It is a scaled-down version of Microsoft SQL Server 7.0 or 2000 which is free for non-commercial use as well as certain limited commercial use. It was introduced at Microsoft TechEd in May 1999, and was included as part of Microsoft Office 2000 Developer Edition. Its successor, SQL Server Express was released in November 2005. Vendor support of MSDE ended on April 8, 2008.

MSDE was initially designed by (then) Microsoft Program Manager Jeff Alger and later implemented by Peter Byrne (core), Ronald Martinsen (core/setup), and Mike Maringas (setup). Alger and Martinsen are the co-inventors who hold the patent.

The initial release of MSDE is called the "Microsoft Desktop Engine", which is based on SQL Server 7.0 and was positioned as an alternative to using Microsoft Access's Microsoft Jet Database Engine with a focus on its ability to operate as a client–server application instead of requiring direct access to the file system which the Jet database resided on. Microsoft Access, the company's most popular database tool at the time, was expanded for its Office 2000 release to incorporate using Microsoft Desktop Engine as its back-end data store. This design was promoted by Microsoft as a solution for small workgroups that may eventually grow to require the full SQL Server product. This initial release of MSDE also included the Data Transformation Services Wizard, which provided the ability to use OLE DB and ODBC data sources to transfer data between SQL Server 7.0 and MSDE. Supported operating systems at the time of its release included Windows 95, Windows 98, and Windows NT 4.0 Service Pack 4, and was available for both x86 and Alpha architectures.

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