Actualidad informatica mysql

MySQL Reference Manual

Copyright c 1997-2000 TcX AB, Detron HB and MySQL Finland AB

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Chapter 1: General Information about MySQL

1 General Information about MySQL
This is the MySQL reference manual; it documents MySQL version 3.23.25-beta. As MySQL is work in progress, the manual gets updated frequently. There is a very good chance that this version is out of date, unless you arelooking at it online. The most recent version of this manual is available at http://www.mysql.com/documentation/ in many different formats. If you have a hard time finding information in the manual, you can try the searchable PHP version at http://www.mysql.com/documentation/manual.php . MySQL is a very fast, multi-threaded, multi-user and robust SQL (Structured Query Language) database server. MySQLis free software. It is licensed with the GNU GENERAL PUBLIC LICENSE http://www.gnu.org/. See Chapter 3 [Licensing and Support], page 27. The MySQL home page (http://www.mysql.com/) provides the latest information about MySQL. The following list describes some useful sections of the manual: • For a discussion of MySQL’s capabilities, see Section 1.5 [Features], page 7. • For installationinstructions, see Chapter 4 [Installing], page 35. For tips on porting MySQL to new architectures or operating systems, see Appendix H [Porting], page 570. • For information about upgrading from a 3.21 release, see Section 4.16.2 [Upgradingfrom-3.21], page 104. • For a tutorial introduction to MySQL, see Chapter 9 [Tutorial], page 271. • For examples of SQL and benchmarking information, see thebenchmarking directory (‘sql-bench’ in the distribution). • For a history of new features and bug fixes, see Appendix E [News], page 508. • For a list of currently known bugs and misfeatures, see Appendix F [Bugs], page 563. • For future plans, see Appendix G [TODO], page 565. • For a list of all the contributors to this project, see Appendix D [Credits], page 502. IMPORTANT: Reports of errors (often calledbugs), as well as questions and comments should be sent to the mailing list at mysql@lists.mysql.com. See Section 2.3 [Bug reports], page 22. The mysqlbug script should be used to generate bug reports. For source distributions, the mysqlbug script can be found in the ‘scripts’ directory. For binary distributions, mysqlbug can be found in the ‘bin’ directory. If you have any suggestions concerningadditions or corrections to this manual, please send them to the manual team at (docs@mysql.com). This is a reference manual; it does not provide general instruction on SQL or relational database concepts. If you want general information about SQL, see Section 1.8 [GeneralSQL], page 13. For books that focus more specifically on MySQL, see Section 1.4 [MySQLBooks], page 5. Version: 3.23.25-betaPrinted: 14 September 2000

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Chapter 1: General Information about MySQL

1.1 What is MySQL

MySQL is a database management system. A database is a structured collection of data. It may be anything from a simple shopping list to a picture gallery or the vast amounts of information in a corporate network. To add, access and process data stored in a computer database, you need a databasemanagement system such as MySQL. Since computers are very good at handling large amounts of data, database management plays a central role in computing, as stand-alone utilities, or as parts of other applications. MySQL is a relational database management system. A relational database stores data in separate tables rather than putting all the data in one big storeroom. This adds speed and flexibility.The tables are linked by defined relations making it possible to combine data from several tables on request. The SQL part of MySQL stands for "Structured Query Language" the most common standardized language used to access databases. MySQL is Open Source Software Open source means that it is possible for anyone to use and modify. Anybody can download MySQL from the Internet and use it without...