Jump to content

MySQL: Difference between revisions

From Wikipedia, the free encyclopedia
Browse history interactively
← Previous editNext edit →
Content deleted Content added
VisualWikitext
Pegasos2 (talk | contribs)
366 edits
No edit summary
m clarify ambiguous sentence
Line 19: Line 19:
The project has made its [[source code]] available under the terms of the [[GNU General Public License]], as well as under a variety of [[proprietary software|proprietary]] agreements. MySQL is owned and sponsored by a single [[Business|for-profit]] firm, the [[Sweden|Swedish]] company [[MySQL AB]], now a [[subsidiary]] of [[Sun Microsystems]]<ref name="sunacquire">[http://www.sun.com/aboutsun/pr/2008-02/sunflash.20080226.1.xml ''Sun Microsystems Announces Completion of MySQL Acquisition; Paves Way for Secure, Open Source Platform to Power the Network Economy''], Sun Microsystems Press release, February 26, 2008</ref>. {{As of | 2009}} [[Oracle Corporation]] began the process of acquiring Sun Microsystems.
The project has made its [[source code]] available under the terms of the [[GNU General Public License]], as well as under a variety of [[proprietary software|proprietary]] agreements. MySQL is owned and sponsored by a single [[Business|for-profit]] firm, the [[Sweden|Swedish]] company [[MySQL AB]], now a [[subsidiary]] of [[Sun Microsystems]]<ref name="sunacquire">[http://www.sun.com/aboutsun/pr/2008-02/sunflash.20080226.1.xml ''Sun Microsystems Announces Completion of MySQL Acquisition; Paves Way for Secure, Open Source Platform to Power the Network Economy''], Sun Microsystems Press release, February 26, 2008</ref>. {{As of | 2009}} [[Oracle Corporation]] began the process of acquiring Sun Microsystems.


MySQL is often used in [[free software]] projects that require a full-featured database management system, such as [[WordPress]], [[phpBB]] and other software built on the [[LAMP (software bundle)|LAMP]] software stack. It is also used in many high-profile, large-scale [[World Wide Web]] products including [[Wikipedia]], [[Google]] and [[Facebook]].
MySQL is often used in [[free software]] projects that require a full-featured database management system, including projects such as [[WordPress]], [[phpBB]] and other software built on the [[LAMP (software bundle)|LAMP]] software stack. It is also used in many high-profile, large-scale [[World Wide Web]] products including [[Wikipedia]], [[Google]] and [[Facebook]].


== Uses ==
== Uses ==

Revision as of 00:23, 30 December 2009

MySQL
Developer(s)Sun Microsystems
Initial releaseMay 23, 1995 (1995-05-23)
Repository
Written inC, C++
Operating systemCross-platform
Available inEnglish
TypeRDBMS
LicenseGNU General Public License (version 2, with linking exception) or proprietary EULA
Websitewww.mysql.com

MySQL is a relational database management system (RDBMS)[1] that has more than 11 million installations.[2][3] MySQL is named after Monty Widenius's daughter My. The program runs as a server providing multi-user access to a number of databases. MySQL is officially Template:PronEng (My S-Q-L), but often Template:PronEng (My SeQueL).[4]

The project has made its source code available under the terms of the GNU General Public License, as well as under a variety of proprietary agreements. MySQL is owned and sponsored by a single for-profit firm, the Swedish company MySQL AB, now a subsidiary of Sun Microsystems[5]. As of 2009 Oracle Corporation began the process of acquiring Sun Microsystems.

MySQL is often used in free software projects that require a full-featured database management system, including projects such as WordPress, phpBB and other software built on the LAMP software stack. It is also used in many high-profile, large-scale World Wide Web products including Wikipedia, Google and Facebook.

Uses

Many web applications use MySQL as the database component of a LAMP software stack. Its popularity for use with web applications is closely tied to the popularity of PHP, which is often combined with MySQL. Several high-traffic web sites (including Flickr[6], Facebook,[7][8] Wikipedia[9], Google[10] (though not for searches), Nokia[11] and YouTube[12]) use MySQL for data storage and logging of user data.

Platforms and interfaces

The MySQL Administrator in Linux

MySQL code uses C and C++. The SQL parser uses yacc and a home-brewed lexer, sql_lex.cc[13]

MySQL works on many different system platforms, including AIX, BSDi, FreeBSD, HP-UX, i5/OS, Linux, Mac OS X, NetBSD, Novell NetWare, OpenBSD, OpenSolaris, eComStation, OS/2 Warp, QNX, IRIX, Solaris, Symbian, SunOS, SCO OpenServer, SCO UnixWare, Sanos, Tru64 and Microsoft Windows. A port of MySQL to OpenVMS also exists.[14]

All major programming languages with language-specific APIs include Libraries for accessing MySQL databases. In addition, an ODBC interface called MyODBC allows additional programming languages that support the ODBC interface to communicate with a MySQL database, such as ASP or ColdFusion. The MySQL server and official libraries are mostly implemented in ANSI C/ANSI C++.

To administer MySQL databases one can use the included command-line tool (commands: mysql and mysqladmin). Potential users may also download from the MySQL site: GUI administration tools: MySQL Administrator, MySQL Migration Toolkit and MySQL Query Browser. The GUI tools are now included in one package called MySQL GUI Tools.

In addition to the above-mentioned tools developed by MySQL AB, several other commercial and non-commercial tools integrate with MySQL. Examples include Navicat Free Lite Edition, AnySQL Maestro Freeware Edition or SQLyog Community Edition, they are free desktop based GUI tools, and phpMyAdmin, a free Web-based administration interface implemented in PHP.

Deployment

MySQL can be built and installed manually from source code, but this can be tedious so it is more commonly installed from a binary package unless special customizations are required. On most Linux distributions the package management system can download and install MySQL with minimal effort, though further configuration is often required to adjust security and optimization settings.

Though MySQL began as a low-end alternative to more powerful proprietary databases, it has gradually evolved to support higher-scale needs as well.

It is still most commonly used in small to medium scale single-server deployments, either as a component in a LAMP based web application or as a standalone database server. Much of MySQL's appeal originates in its relative simplicity and ease of use, which is enabled by an ecosystem of open source tools such as phpMyAdmin or a pre-integrated TurnKey MySQL appliance that is ready-to-use[15] without manual configuration or setup.

In the medium range, MySQL can be scaled by deploying it on more powerful hardware, such as a multi-processor server with gigabytes of memory.

There are however limits to how far performance can scale on a single server, so on larger scales, multi-server MySQL deployments are required to provide improved performance and reliability. A typical high-end configuration can include a powerful master database which handles data write operations and is replicated to multiple slaves that handle all read operations.[16] The master server synchronizes continually with its slaves so in the event of failure a slave can be promoted to become the new master, minimizing downtime. Further improvements in performance can be achieved by caching the results from database queries in memory using memcached, or breaking down a database into smaller chunks called shards which can be spread across a number of distributed server clusters.[17]

Features

As of April 2009, MySQL offers MySQL 5.1 in two different variants: the MySQL Community Server and Enterprise Server.[18] They have a common code base and include the following features:

The developers release monthly versions of the MySQL Enterprise Server. The sources can be obtained either from MySQL's customer-only Enterprise site or from MySQL's Bazaar repository, both under the GPL license. The MySQL Community Server is published on an unspecified schedule under the GPL and contains all bug fixes that were shipped with the last MySQL Enterprise Server release. Binaries are no longer provided by MySQL for every release of the Community Server.[20][21]

Distinguishing features

MySQL implements the following features, which some other RDBMS systems may not:

  • Multiple storage engines, allowing one to choose the one that is most effective for each table in the application (in MySQL 5.0, storage engines must be compiled in; in MySQL 5.1, storage engines can be dynamically loaded at run time):
  • Commit grouping, gathering multiple transactions from multiple connections together to increase the number of commits per second.

Product History

Milestones in MySQL development include:

  • Original development of MySQL by Michael Widenius and David Axmark beginning in 1994 [22]
  • First internal release on 23 May 1995
  • Windows version was released on 8 January 1998 for Windows 95 and NT
  • Version 3.23: beta from June 2000, production release January 2001
  • Version 4.0: beta from August 2002, production release March 2003 (unions)
  • Version 4.01: beta from August 2003, Jyoti adopts MySQL for database tracking
  • Version 4.1: beta from June 2004, production release October 2004 (R-trees and B-trees, subqueries, prepared statements)
  • Version 5.0: beta from March 2005, production release October 2005 (cursors, stored procedures, triggers, views, XA transactions)
The developer of the Federated Storage Engine states that "The Federated Storage Engine is a proof-of-concept storage engine",[23] but the main distributions of MySQL version 5.0 included it and turned it on by default. Documentation of some of the short-comings appears in "MySQL Federated Tables: The Missing Manual".
  • Sun Microsystems acquired MySQL AB on 26 February 2008.[5]
  • Version 5.1: production release 27 November 2008 (event scheduler, partitioning, plugin API, row-based replication, server log tables)
Version 5.1 contained 20 known crashing and wrong result bugs in addition to the 35 present in version 5.0.[24]
MySQL 5.1 and 6.0 showed poor performance when used for data warehousing — partly due to its inability to utilize multiple CPU cores for processing a single query.[25].

Future releases

The MySQL 6 roadmap outlines support for:

  • Referential integrity and Foreign key support for all storage engines is targeted for release in MySQL 6.1 (although it has been present since version 3.23.44 for InnoDB).
  • Support for supplementary Unicode characters, beyond the 65,536 characters of the Basic Multilingual Plane (BMP); announced for MySQL 6.0.
  • A new storage engine called Falcon. A preview of Falcon is available on MySQL's website.

The 2006 roadmap for future versions plans support for parallelization.[26]

Support and licensing

Via MySQL Enterprise MySQL AB offers support itself, including a 24/7 service with 30-minute response time. The support team has direct access to the developers as necessary to handle problems. In addition, it hosts forums and mailing lists, employees and other users are often available in several IRC channels providing assistance.

In addition to official product support from Sun, other companies offer support and services related to usage of MySQL. For example, Percona offers services related to optimization and Monty Program Ab offers non-recurring engineering.

Buyers of MySQL Enterprise have access to binaries and software certified for their particular operating system, and access to monthly binary updates with the latest bug-fixes. Several levels of Enterprise membership are available, with varying response times and features ranging from how to and emergency support through server performance tuning and system architecture advice. The MySQL Network Monitoring and Advisory Service monitoring tool for database servers is available only to MySQL Enterprise customers.

Potential users can install MySQL Server as free software under the GNU General Public License (GPL), and the MySQL Enterprise subscriptions include a GPL version of the server, with a traditional proprietary version available on request at no additional cost for cases where the intended use is incompatible with the GPL.[27]

Both the MySQL server software itself and the client libraries use dual-licensing distribution. Users may choose the GPL,[28] which MySQL has extended with a FLOSS License Exception. It allows Software licensed under other OSI-compliant Open Source licenses, which are not compatible to the GPL, to link against the MySQL client libraries.[29]

Customers that do not wish to follow the terms of the GPL may purchase a proprietary license.[30]

Like many open-source programs, MySQL has trademarked its name, which others may use only with the trademark holder's permission.

Corporate backing history

In October 2005, Oracle Corporation acquired Innobase OY, the Finnish company that developed the InnoDB storage engine that allows MySQL to provide such functionality as transactions and foreign keys. After the acquisition, an Oracle press release[31] mentioned that the contracts that make the company's software available to MySQL AB would be due for renewal (and presumably renegotiation) some time in 2006. During the MySQL Users Conference in April 2006, MySQL issued a press release that confirmed that MySQL and Innobase OY agreed to a "multi-year" extension of their licensing agreement.[32]

In February 2006, Oracle Corporation acquired Sleepycat Software,[33] makers of the Berkeley DB, a database engine providing the basis for another MySQL storage engine.

In April 2009, Oracle Corporation entered into an agreement to purchase Sun Microsystems,[34] current owners of the MySQL intellectual property. Sun's board of directors unanimously approved the deal, it was also approved by Sun's shareholders, and by the U.S. government on August 20, 2009.[35] On December 14 2009, Oracle pledged to continue to enhance MySQL.[36] In Europe the merge is under scrutiny by EU antitrust regulators, whose main concerns are on conflict of interests with existing database software by Oracle. Michael Widenius, father of MySQL, launched a petition to pledge EU Commission to stop the deal.

See also

Template:Fossportal

References

  1. ^ Robin Schumacher, Arjen Lentz. "Dispelling the Myths". MySQL AB. Retrieved 2007-02-10.
  2. ^ Charles Babcock "Sun Locks Up MySQL, Looks To Future Web Development". InformationWeek. Retrieved 2008-02-27.
  3. ^ "Top Reasons for Product Managers to Embed MySQL". Retrieved 2009-12-09.
  4. ^ "What is MySQL?, MySQL 5.0 Reference Manual". MySQL AB. Retrieved 2007-02-10.
  5. ^ a b Sun Microsystems Announces Completion of MySQL Acquisition; Paves Way for Secure, Open Source Platform to Power the Network Economy, Sun Microsystems Press release, February 26, 2008
  6. ^ "YouTube, Flickr, and Wikipedia to Share their Secrets of Success at the 2007 MySQL Conference & Expo". MySQL. 10 April 2007. Retrieved 2009-12-09.
  7. ^ Sobel, Jason (21 December 2007). "Keeping Up". Facebook Blog. {{cite web}}: Unknown parameter |ac cessdate= ignored (help)
  8. ^ Malik, Om (25 April 2008). "Facebook's Insatiable Hunger for Hardware". GigaOM. Retrieved 2008-10-30.
  9. ^ "Wikimedia servers - Overall system architecture". Retrieved 2009-09-11.
  10. ^ Claburn, Thomas (24 April 2007). "Google Releases Improved MySQL Code". Information Week. Retrieved 2008-11-30.
  11. ^ http://www.mysql.com/customers/view/?id=579
  12. ^ http://www.mysql.com/customers/industry/?id=85
  13. ^ "MySQL Internals Manual". Dev.mysql.com. 2009-03-04. Retrieved 2009-06-08.
  14. ^ Jean-François Piéronne. "PCSI Kits of Open Source Software for OpenVMS". Pi-net.dyndns.org. Retrieved 2009-06-08.
  15. ^ "MySQL Appliance". TurnKey Linux Virtual Appliance Library. Retrieved 2009-12-09.
  16. ^ "The future of replication in MySQL". Facebook. Retrieved 2009-12-09.
  17. ^ "Database Sharding". Code Futures. Retrieved 2009-12-09.
  18. ^ "Which Should I Use: MySQL Enterprise or MySQL Community Server?". MySQL AB. Retrieved 2009-04-08.
  19. ^ "4.6.9. mysqlhotcopy - A Database Backup Program". MySQL 5.0 Reference Manual. Sun Microsystems. Retrieved 2009-09-23. mysqlhotcopy is a Perl script [...]. It uses Lock Tables, Flush Tables, and cp or scp to make a database backup quickly [...] but it can be run only on the same machine where the database directories are located. mysqlhotcopy works only for backing up MyISAM and Archive tables. It runs on Unix and NetWare. {{cite web}}: Cite has empty unknown parameters: |month= and |coauthors= (help)
  20. ^ "Peter Zaitsev's blog". Mysqlperformanceblog.com. Retrieved 2009-06-08.
  21. ^ "Kaj Arnö's reply". Planetmysql.org. Retrieved 2009-06-08.
  22. ^ "Five Questions With Michael Widenius - Founder And Original Developer of MySQL". Opensourcereleasefeed.com. Retrieved 2009-06-08.
  23. ^ "capttofu: FederatedX Pluggable Storage Engine Released!". Capttofu.livejournal.com. Retrieved 2009-04-03.
  24. ^ "Archives - Oops, we did it again (MySQL 5.1 released as GA wi". Planet MySQL. 2008-11-29. Retrieved 2009-04-03.
  25. ^ "TPC-H Run on MySQL 5.1 and 6.0 | MySQL Performance Blog". MySQL Performance Blog. Retrieved 2009-06-08.
  26. ^ "Does MySQL support query parallelisation?". Forums.mysql.com. Retrieved 2009-06-08.
  27. ^ "Must I purchase MySQL Enterprise under MySQL's Commercial License in order to receive support?". MySQL AB.
  28. ^ "MySQL AB :: MySQL Open Source License". Mysql.com. Retrieved 2009-06-08.
  29. ^ "MySQL AB :: FLOSS License Exception". Mysql.com. Retrieved 2009-06-08.
  30. ^ "MySQL AB :: MySQL Commercial License". Mysql.com. Retrieved 2009-06-08.
  31. ^ "Oracle Plans to Increase Support for Open Source Software". Oracle and InnoDB.
  32. ^ "MySQL to Promote New Open Source DB Engines from its Partners and Dev Community". MySQL AB.
  33. ^ "Oracle Buys Sleepycat, Is JBoss Next?". Charles Babcock.
  34. ^ "Oracle to Buy Sun". Sun Microsystems Press Release.
  35. ^ "Oracle wins U.S. approval to buy Sun Microsystems". Reuters. August 20, 2009. Retrieved 2009-09-30.
  36. ^ http://news.cnet.com/8301-1001_3-10414686-92.html
Wikibooks has more on the topic of: MySQL
Wikimedia Commons has media related to MySQL.
Retrieved from "https://en.wikipedia.org/w/index.php?title=MySQL&oldid=334817897"