Microsoft SQL Server
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Microsoft SQL Server is a relational database management system produced by Microsoft. It supports a superset of Structured Query Language SQL, the most common database language. It is commonly used by businesses for small to medium sized databases, and in the past 5 years large enterprise databases and competes with other relational database products for this market segment.
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History
The code base for Microsoft SQL Server originated in Sybase SQL Server, and was Microsoft's entry to the enterprise-level database market, competing against Oracle, IBM, and Sybase. The first version was SQL Server for OS/2 (about 1989) which was essentially the same as Sybase SQL Server 4.0 on Unix, VMS, etc. Microsoft SQL Server 4.2 was shipped around 1993 (available bundled with Microsoft OS/2 version 1.3).
About the time Windows NT was coming out, Sybase and Microsoft parted ways and pursued their own design and marketing schemes. Later, Sybase changed the name of its product to Adaptive Server Enterprise to avoid confusion with Microsoft SQL Server. Until 1994 Microsoft's SQL Server carried three Sybase copyright notices as an indication of its origin.
Several revisions have been done independently since with improvements for SQL Server. SQL Server 7.0 was the first true GUI based database server, and a variant of SQL Server 2000 was the first commercial database for the Intel IA64 architecture. During this time there was a rivalry between Microsoft and Oracle's servers for winning the market over enterprise customers.
The current version, Microsoft SQL Server 2000, was released in August of 2000. Microsoft is beta testing its successor, SQL Server 2005. This is scheduled to launch during the week of 7th November 2005, alongside Visual Studio 2005 and BizTalk Server 2006. The June CTP (Community Technology Preview) release is currently available for free download.
Versions for Windows
- 1993 - SQL Server 4.2
- 1995 - SQL Server 6.0, codenamed SQL95
- 1996 - SQL Server 6.5, codenamed Hydra
- 1998 - SQL Server 7.0, codenamed Sphinx
- 1999 - SQL Server 7.0 OLAP, codenamed Plato
- 2000 - SQL Server 2000 32-bit, codenamed Shiloh
- 2003 - SQL Server 2000 64-bit, codenamed Liberty
- 2005 - SQL Server 2005, codenamed Yukon (not released yet)
Description
MS SQL Server uses a variant of SQL called T-SQL, or Transact-SQL, a superset of SQL-92 (The ISO standard for SQL, certified in 1992). T-SQL mainly adds additional syntax for use in stored procedures, and affects the syntax of transactions support. (Note that SQL standards require (ACID) Atomic, Consistent, Isolated, Durable transactions.) MS SQL Server and Sybase/ASE both communicate over networks using an application-level protocol called Tabular Data Stream (TDS). The TDS protocol has also been implemented by the FreeTDS project ([1] (http://www.freetds.org)) in order to allow more kinds of client applications to communicate with MS SQL Server and Sybase databases. MS SQL Server also supports Open Database Connectivity (ODBC).
Variants
A stripped down version of Microsoft SQL Server known as MSDE (Microsoft SQL Server Desktop Engine) is distributed with products such as Visual Studio, Visual FoxPro, Microsoft Access, MS Web Matrix, and other products. MSDE has some restrictions: a limit of 2 GB databases, and it comes with no tools to administer it. It also has a workload governor which reduces its speed once you exceed 8 concurrent workloads on the engine.
Microsoft recently announced the successor to MSDE, dubbed SQL Server Express. Similar to MSDE, SQL Express includes all the core functionality of SQL Server but places restrictions on the scale of databases. It will only utilize a single CPU, 1 GB of RAM, and imposes a maximum size of 4 GB on databases. SQL Express also doesn't include enterprise features such as Analysis Services, Reporting Services, Data Transformation Services, and Notification Services. Unlike MSDE, SQL Express includes a management console, called SQL Server Express Manager. A beta version of SQL Server Express is now available for download.
Slammer worm
A computer worm, named the SQL slammer worm, which exploited a previously patched security vulnerability in this system was discovered in January, 2003, and caused a large Internet slowdown on January 24. It is possible that this worm caused the largest degradation in Internet performance since the infamous Morris worm (November 2, 1988).
See also
- Windows Server System
- List of relational database management systems
- Comparison of relational database management systems
External links
- SQL Server Official Site (http://www.microsoft.com/sql/default.asp)
- SQL Server 2005 Express Beta download (http://msdn.microsoft.com/express/)
- SQL Server June 2005 Community Technology Preview (http://www.microsoft.com/sql/2005/productinfo/ctp.mspx)de:MSSQL
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