Various databases.
Apache CouchDB, commonly referred to as CouchDB, is a free and open source document-oriented database written in the Erlang programming language. It is designed for local replication and to scale vertically along a wide range of devices.
Overview
CouchDB is most similar to other document stores like MongoDB and Lotus Notes. It is not a relational database management system. Instead of storing data in rows and columns, the database manages a collection of JSON documents. The documents in a collection need not share a schema, but retain query abilities via views. Views are defined with aggregate functions and filters are computed in parallel, much like MapReduce.
Views are generally stored in the database and their indexes updated continuously, although queries may introduce temporary views. CouchDB supports a view system using external socket servers and a JSON based protocol. As a consequence, view servers have been developed in a series of languages.
CouchDB exposes a RESTful HTTP API and a large number of pre-written clients are available. Additionally, a plugin architecture allows for using different computer languages as the view server such as JavaScript (default), PHP, Ruby, Python and Erlang. Support for other languages can be easily added.
CouchDB was accepted into Apache incubation in February 2008 and became a top level project in November 2008. Despite its low version number of 0.10, it is already in use in many software projects and web sites, including Ubuntu, where it is used to synchronize address and bookmark data.
(From http://en.wikipedia.org/wiki/CouchDB on January 09, 2010)
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END OF TERMS AND CONDITIONS
Original Authors:
Damien Katz, Jan Lehnardt, Noah Slater, Christopher Lenz, J. Chris Anderson
Current committers:
Original developer and remains the project lead.
Worked on the original UNIX port and now works on all ends in CouchDB.
He is a freelancing CouchDB consultant and gives presentations around the
world.
Developed and maintains the Autotools build system and application
infrastructure. He is CouchDB’s release manager and maintains a number of
related packages for Debian GNU/Linux.
Developed and maintains Futon, the Web administration console. He works on
the JavaScript view engine, SpiderMonkey and MochiWeb integration in
addition to an external Python client.
Upgraded the Erlang JSON term format. Integrates community patches,
particularly related to the HTTP API and the MapReduce system. Gives talks and
presentations about CouchDB, with an eye toward recruiting more developers.
Developed features for the HTTP API as well as helped with recent upgrades
to the MapReduce system. Spends time tracking down various bugs reported in
JIRA.
Adam Kocoloski
Maintains and extends the replicator. Hacks on various other parts of the
core database.
Mark Hammond
Windows support.
Developed various authentication features including cookie-based
authentication and OAuth support.
MySQL is a relational database management system (RDBMS) which has more than 11 million installations. The program runs as a server providing multi-user access to a number of databases.
MySQL is owned and sponsored by a single for-profit firm, the Swedish company MySQL AB, now a subsidiary of Sun Microsystems,[3] which holds the copyright to most of the codebase. The project's source code is available under terms of the GNU General Public License, as well as under a variety of proprietary agreements.
"MySQL" is officially pronounced /maɪˌɛskjuːˈɛl/ (My S Q L), not "My sequel" /maɪˈsiːkwəl/. This adheres to the official ANSI pronunciation; SEQUEL was an earlier IBM database language, a predecessor to the SQL language. The company does not take issue with the pronunciation "My sequel" or other local variations.
History
This article or section needs to be updated. Please update the article to reflect recent events or newly available information, and remove this template when finished.
Milestones in MySQL development include:
MySQL was first released internally on 23 May 1995
Windows version was released on January 8, 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 4.1: 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)
Version 5.1: currently pre-production (since November 2005) (event scheduler, partitioning, plugin API, row-based replication, server log tables)
Sun Microsystems acquired MySQL AB on 26 February 2008.
Future releases
The MySQL 5.1 roadmap outlines support for:
Pluggable storage engine API
Partitioning
Event Scheduling
XML functions
Row-based replication
Support for parallelization is also part of the roadmap for future versions.
Support for supplementary Unicode characters, beyond the 65536 characters of the Basic Multilingual Plane (BMP) is announced for MySQL 6.0.
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).
The current MySQL 5.1 development release is 5.1.29.
A new storage engine is also in the works, called Falcon. A preview of Falcon is already available on MySQL's website.
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.
Buyers of MySQL Enterprise have access to binaries and software that is 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.
MySQL Server is available 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.
Both the MySQL server software itself and the client libraries are distributed under a dual-licensing format. Users may choose the GPL, 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.
Customers that do not wish to be bound to the terms of the GPL may choose to purchase a proprietary license.
Like many open-source programs, the name "MySQL" is trademarked and may only be used with the trademark holder's permission.
Some users have independently continued to develop earlier versions of the client libraries, which was distributed under the less-restrictive GNU Lesser General Public License (LGPL).
Issues
There has been some controversy regarding the distribution of GPL licensed MySQL library files with other open source applications. The biggest controversy arose with PHP, which has a license incompatible with the GPL. This was later resolved when MySQL created a license exception that explicitly allows the inclusion of the MySQL client library in open source projects that are licensed under a number of OSI-compliant Open Source licenses, including the PHP License.
In September 2005, MySQL AB and SCO forged a partnership for "joint certification, marketing, sales, training and business development work for a commercial version of the database for SCO's new OpenServer 6 version of Unix". SCO raised controversy beginning in 2003 with a number of high-profile lawsuits related to the Linux Operating System. Various MySQL employees expressed that the company was committed to serving its end users, regardless of their operating system choice, that the company would leave it to the courts to resolve the SCO licensing controversy, and that other common open source databases have also been ported to, and support, SCO OpenServer.
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. A press release by Oracle that was issued after the acquisition, 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 which confirmed that MySQL and Innobase OY agreed to a multi-year extension of their licensing agreement.
In February 2006, Oracle Corporation acquired Sleepycat Software, makers of the Berkeley DB, a database engine onto which another MySQL storage engine was built.
Criticism
It has been suggested that some of the information in this article's Criticism or Controversy section(s) be merged into other sections to achieve a more neutral presentation. (Discuss)
MySQL's divergence from the SQL standard regarding the treatment of NULL values and default values has been criticized. Its handling of dates in versions prior to 5.0 allows storing a date with a day beyond the last day of a month with fewer than 31 days, and arithmetic operations are vulnerable to either integer overflow or floating point truncation. Since version 5 of the server, the treatment of illegal values varies according to use of the "SQL Mode" set in the server, which is by default set to the unusually tolerant state that critics dislike.
When the beta version of MySQL 5.0 was released in March 2005, David Axmark, a co-founder of MySQL, said that "People have been criticizing MySQL since we started for not having stored procedures, triggers and views," and "We're fixing 10 years of criticism in one release." MySQL 5.0's 13 October build 5.0.15 was released for production use on 24 October 2005, after more than two million downloads in the 5.0 beta cycle.
Critical bugs sometimes do not get fixed for long periods of time. An example is a bug with status critical existing since 2003.
MySQL shows poor performance when used for Data Warehousing; this is partly due to inability to utilize multiple CPU cores for processing a single query.
The developer of the Federated Storage Engine states that "The Federated Storage Engine is a proof-of-concept storage engine" [1], though it was included and turned on by default in the main distributions of MySQL version 5.0. Some of the short-comings are documented in the "MySQL Federated Tables: The Missing Manual".
(From http://en.wikipedia.org/wiki/Mysql on November 25, 2008)
David Axmark is one of the founders of MySQL AB and a developer of the Free Software database server, MySQL. He has been involved with MySQL development from its beginning along with the fellow co-founder Michael Widenius.
David currently focuses on Open Source Licensing aspects, community relations and evangelism.
David has been involved with Free Software since 1980 and is committed to developing a successful business model using Free Open Source Software. [1]
(From wikipedia November 2, 2008)
Ulf Michael Widenius (often called Monty), born March 3, 1962, in Helsinki, Finland, is the main author of the original version of the open-source MySQL database and a founding member of the MySQL AB company.
After studying at (although not graduating from) the Helsinki University of Technology, Widenius started working for Tapio Laakso Oy in 1981. In 1985 he founded TCX DataKonsult AB (a Swedish data warehousing company) with Allan Larsson.[1] In 1995 he began writing the first version of the MySQL database with David Axmark, released in 1996. He is the co-author of the MySQL Reference Manual, published by O'Reilly in June 2002; and in 2003 he was awarded the Finnish Software Entrepreneur of The Year prize. Until MySQL AB's sale to Sun Microsystems in January 2008,[2] he was the chief technical officer of MySQL AB and still one of the primary forces behind the ongoing development of MySQL. During the 2007 MySQL Users Conference & Expo, Michael Widenius was awarded the honor of being the world's first MySQL Fellow [3] — the highest honor one can achieve from MySQL AB.
He lives in Helsinki with his second wife Anna and daughter Maria, and has a daughter My (MySQL is named after Monty Widenius's daughter, according to "History of MySQL") and a son Max (possibly giving the name for MaxDB) from his first marriage. According to the MySQL documentation's history, it is unclear and a mystery to MySQL founders themselves where the "My" prefix originated.
(from wikipedia November 2, 2008)
PostgreSQL is an object-relational database management system (ORDBMS). It is released under a BSD-style license and is thus free software. As with many other open-source programs, PostgreSQL is not controlled by any single company, but relies on a global community of developers and companies to develop it.
Product name
The mixed-capitalization of the PostgreSQL name can confuse some people on first viewing. The several pronunciations of 'SQL' can lead to this confusion. PostgreSQL's developers pronounce it /poːst ɡɹɛs kjuː ɛl/; (Audio sample, 5.6k MP3). It is also common to hear it abbreviated as simply "postgres", which was its original name. Because of ubiquitous support for the SQL Standard amongst most relational databases, the community considered changing the name back to Postgres. However, the PostgreSQL Core Team announced in 2007 that the product would continue to be named PostgreSQL. The name refers to the project's origins as a "post-Ingres" database, the original authors having also developed the Ingres database.
History
PostgreSQL evolved from the Ingres project at University of California, Berkeley. In 1982, the project leader, Michael Stonebraker, left Berkeley to commercialize Ingres. He returned to Berkeley in 1985 and started a post-Ingres project to address the problems with contemporary database systems that had become increasingly clear during the early 1980s. The new project, Postgres, aimed to add the fewest features needed to completely support types. These features included the ability to define types and to fully describe relationships – something used widely before but maintained entirely by the user. In Postgres, the database "understood" relationships, and could retrieve information in related tables in a natural way using rules. Postgres used many ideas of Ingres but not its code.
Starting in 1986, the team published a number of papers describing the basis of the system, and by 1988 had a prototype version. The team released version 1 to a small number of users in June 1989, then version 2 with a re-written rules system in June 1990. Version 3, released in 1991, again re-wrote the rules system, and added support for multiple storage managers and an improved query engine. By 1993 the great number of users began to overwhelm the project with requests for support and features. After releasing version 4 — primarily a cleanup — the project ended.
But open-source developers could obtain copies and develop the system further, because Berkeley had released Postgres under the BSD license. In 1994, Berkeley graduate students Andrew Yu and Jolly Chen replaced the Ingres-based QUEL query language interpreter with one for the SQL query language, creating Postgres95. The code was released on the web.
In July 1996, Marc Fournier at Hub.Org Networking Services provided the first non-university development server for the open source development effort. Along with Bruce Momjian and Vadim B. Mikheev, work began to stabilize the code inherited from Berkeley. The first open source version was released on August 1, 1996.
In 1996, the project was renamed to PostgreSQL to reflect its support for SQL. The first PostgreSQL release formed version 6.0 in January 1997. Since then, the software was maintained by a group of database developers and volunteers around the world, coordinating via the Internet.
Although the license allowed for the commercialization of Postgres, the code did not develop commercially at first — somewhat surprisingly considering the advantages Postgres offered. The main offshoot originated when Paula Hawthorn (an original Ingres team member who moved from Ingres) and Michael Stonebraker formed Illustra Information Technologies to commercialize Postgres.
In 2000, former Red Hat investors created the company Great Bridge to commercialize PostgreSQL and compete against commercial database vendors. Great Bridge sponsored several PostgreSQL developers and donated many resources back to the community, but by late 2001 closed due to tough competition from companies like Red Hat and to poor market conditions.
In 2001, Command Prompt, Inc. released Mammoth PostgreSQL, the oldest surviving commercial PostgreSQL distribution. It continues to actively support the PostgreSQL community through developer sponsorships and projects including PL/Perl, PL/php, and hosting of community projects such as the PostgreSQL Build Farm.
In January 2005, PostgreSQL received backing by database vendor Pervasive Software, known for its Btrieve product which was ubiquitous on the Novell NetWare platform. Pervasive announced commercial support and community participation and achieved some success. But in July 2006, it left the PostgreSQL support market.
In mid-2005 two other companies announced plans to commercialize PostgreSQL with focus on separate niche markets. EnterpriseDB added functionality to allow applications written to work with Oracle to be more readily run with PostgreSQL. Greenplum contributed enhancements directed at data warehouse and business intelligence applications, including the BizGres project.
In October 2005, John Loiacono, executive vice president of software at Sun Microsystems, commented: "We're not going to OEM Microsoft but we are looking at PostgreSQL right now," although no specifics were released at that time. By November 2005, Sun had announced support for PostgreSQL. By June 2006, Sun Solaris 10 (6/06 release) shipped with PostgreSQL.
In August 2007, EnterpriseDB announced the Postgres Resource Center and EnterpriseDB Postgres, designed to be a fully configured distribution of PostgreSQL including many contrib modules and add-on components. EnterpriseDB Postgres was renamed to Postgres Plus in March 2008.
The PostgreSQL project continues to make yearly major releases and minor "bugfix" releases, all available under the BSD license, based on contributions from both commercial vendors, support companies, and open source programmers at large.
(From http://en.wikipedia.org/wiki/Postgres on November 25, 2008)
PostgreSQL is released under the BSD license.
PostgreSQL Database Management System
(formerly known as Postgres, then as Postgres95)
Portions Copyright (c) 1996-2009, The PostgreSQL Global Development Group
Portions Copyright (c) 1994, The Regents of the University of California
Permission to use, copy, modify, and distribute this software and its documentation for any purpose, without fee, and without a written agreement is hereby granted, provided that the above copyright notice and this paragraph and the following two paragraphs appear in all copies.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
Different people involved in PostgreSQL
The founders of Postgres
Michael Stonebraker is a computer scientist specializing in database research and development. His career covers, and helped create, the majority of the existing relational database market today. He is also the founder of Ingres, Illustra, Cohera, StreamBase Systems and Vertica and was previously the CTO of Informix. He is also an editor for the book Readings in Database Systems.
Stonebraker earned his bachelor's degree from Princeton University in 1965 and his master's degree and his Ph.D. from the University of Michigan in 1967 and 1971, respectively. He has received several awards, including the IEEE John von Neumann Medal and the very first SIGMOD Edgar F. Codd Innovations Award. In 1994 he was inducted as a Fellow of the Association for Computing Machinery.
Michael Stonebraker was a Professor of Computer Science at University of California, Berkeley for twenty five years where he developed the INGRES and POSTGRES relational database systems. He is currently an adjunct professor at MIT.
Ingres
In 1973 Stonebraker and his colleague Eugene Wong decided to start researching relational database systems after reading a series of seminal papers published by IBM. By the mid-1970s they had produced, using a rotating team of student programmers, a usable system known as Ingres. At the time Ingres was considered "low end" compared to IBM's similar effort, System R, as it ran on Unix-based DEC machines as opposed to the "big iron" IBM mainframes.
However by the early 1980s the performance and capabilities of these low-end machines was seriously threatening IBM's mainframe market, and with it came the ability of Ingres to be a "real" product for a large number of applications. Ingres was offered using a variation of the BSD license for a nominal fee, and soon a number of companies took advantage of this to create commercial versions of Ingres.
This included Stonebraker, who helped found Relational Technology, Inc., later called Ingres Corporation. Later sold to Computer Associates, Ingres was re-established as an independent company in 2005.
Postgres
Upon his return he started a "post-ingres" effort to address the limitations of the relational model, naming the new project Postgres. Postgres offered a number of features that effectively made the database "understand" the data inside it, dramatically improving programmability. Postgres was also offered using a BSD-like license, and the code forms the basis of today's free software, PostgreSQL.
Stonebraker helped commercialize the code, creating Illustra.
Cohera
In the late 1990s, Mike Stonebraker founded Cohera Software, headquartered in Hayward, California. Cohera's initial mission was to build a federated database, an updated approach to integrating data in multiple databases that began with the first attempts at distributed relational databases in the 1980s. The federated database market had not seen significant customer demand by the 1999-2000 time frame, so Cohera was re-focused on delivering industry-specific capabilities on top of the core integration engine. Cohera was ultimately sold in August 2001 to PeopleSoft.
StreamBase
Mike Stonebraker moved to MIT in the late 1990's and set up a project called Aurora (http://www.cs.brown.edu/research/aurora/). Aurora is about data management for streaming data, using a SQL variant called StreamSQL. StreamBase Systems (http://www.streambase.com) is the company he founded to commercialize the technology.
Vertica and C-Store
Another project Stonebraker has been involved in is C-Store, a column-oriented DBMS. The technology is being commercialized by Vertica Systems, which he co-founded and is serving as Chief Technical Officer.
Additional work
On his second return to academia, he initiated the Mariposa project which became the basis of Cohera which was subsequently sold to PeopleSoft.
(From http://en.wikipedia.org/wiki/Michael_Stonebraker on November 25, 2008)