Microsoft SQL Server is a relational database management system produced by Microsoft. It supports Microsoft's version 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 five years — some large enterprise databases.
History
The code base for Microsoft SQL Server (prior to version 7.0) originated in Sybase SQL Server, and was Microsoft's entry to the enterprise-level database market, competing against Oracle, IBM, and Sybase. Microsoft, Sybase and Ashton-Tate teamed up to create and market the first version named SQL Server 4.2 for OS/2 (about 1989) which was essentially the same as Sybase SQL Server 4.0 on Unix, VMS, etc. Microsoft SQL Server for NT v4.2 was shipped around 1992 (available bundled with Microsoft OS/2 version 1.3) and was a simple port from OS/2 to NT. Microsoft SQL Server v6.0 was the first version of SQL Server that was architected for NT and did not include any direction from Sybase.
About the time Windows NT was coming out, Sybase and Microsoft parted ways and pursued their own design and marketing schemes. Microsoft negotiated exclusive rights to all versions of SQL Server written for Microsoft operating systems. 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 was a rewrite away from the legacy Sybase code, 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 2005, was released in November of 2005. The launch took place alongside Visual Studio 2005 and BizTalk Server 2006. The SQL Server 2005 Express edition is currently available for free download. The Microsoft SQL Server product is not just a database, it also contains (as part of the product) an enterprise ETL tool (Integration Services), Reporting Server, OLAP and messaging technologies specifically Service Broker.
Versions for Windows
- 1993 - SQL Server 4.21 for Windows NT
- 1995 - SQL Server 6.0, codenamed SQL95
- 1996 - SQL Server 6.5, codenamed Hydra
- 1999 - 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
- Next release - codenamed Katmai
Description
MS SQL Server uses a variant of SQL called T-SQL, or Transact-SQL, an implementation of SQL-92 (the ISO standard for SQL, certified in 1992) with some extensions. 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]) 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, ASP.NET Web Matrix, and other products. MSDE has some restrictions: a limit of 2 GB databases, and it comes with no GUI 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 released the successor to MSDE, dubbed SQL Server Express. Similar to MSDE, SQL Express includes all the core functionality of SQL Server and the workload governor was removed, 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 per database (log sizes don't count). Microsoft provides a separate download ("feature pack") for the Express edition that includes less feature rich version of Reporting Services. SQL Express also doesn't include enterprise features such as Analysis Services, Data Transformation Services, and Notification Services. Unlike MSDE, SQL Express includes a management console, called SQL Server Management Studio Express.
Competition and Market Analysis
Microsoft's primary competition includes Oracle and IBM DB2 and is currently ranked #3 in revenue share among these "big three" database vendors. Oracle tends to be more competetive with the mid-range database market, especially among the many customers concerned about cross-platform compatibility.
In contrast to many of its competitors, SQL Server runs solely on Microsoft Windows based operating systems. As a result, the relative strength and viability of SQL Server is directly affected by the relative strengths and weaknesses of the Microsoft platform. IBM tends to fare decently in the mid-range market and dominate the high-end market, particularly with its z/OS database which is preeminent for enterprise OLTP. Like Oracle, IBM beats Microsoft in any cross-platform contests by default. However, many large organizations run two or even all three of these vendors' products in some combination. Other commercial competitors include Teradata, Sybase, and IBM Informix.
Recently, open source databases such as MySQL, PostgreSQL and Firebird have further increased the competition among database vendors. These databases offer no-cost and low-cost licensing and, for many clients, offer "good enough" functionality for their database needs. Both Oracle and IBM now offer open source versions of their databases. Although Microsoft has for several years offered a scaled-down, license-free version of its database engine (MSDE in previous versions and MS SQL Server Express in version 2005), Microsoft does not, at this point, offer any true open source software licensing. It does, however, similar to most of its current high profile products, offer source code to companies that become Microsoft Solution Partners with both Non-Disclosure Agreements and subscription based annual fees.
Slammer worm
A computer worm, named the SQL slammer worm, which exploited a previously patched security vulnerability in MS SQL 2000 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).
Sub Products
See also
Further reading
- Kalen Delaney (2001). "Inside SQL Server 2000". Microsoft Press. ISBN 0-7356-0998-5.
- Scalability Experts (2005) "SQL Server 2005 : Changing the Paradigm". Sams ISBN 0-6723-2778-3
- Thomas Rizzo, Adam Machanic, et al (2005) "Pro SQL Server 2005". Apress ISBN 1-59059-477-0
- Fernando Guerrero, Carlos Eduardo Rojas (2001). "Sql Server Programming By Example", QUE ISBN 0-7897-2449-9
- Tony Bain, et al (2004) "Beginning SQL Server 2000 DBA From Novice to Professional", aPress ISBN 1-59059-293-X
External links
