Neo4j

分手后的思念是犯贱 2022-06-18 12:42 356阅读 0赞

**Neo4j** is a [graph database][] management system developed by Neo Technology, Inc. Described by its developers as an [ACID][]\-compliant transactional database with native graph storage and processing,[\[3\]][3] Neo4j is the most popular graph database according to db-engines.com.[\[4\]][4]

Neo4j is available in a [GPL3][]\-licensed [open-source][] "community edition", with [online backup][] and [high availability][] extensions licensed under the terms of the [Affero General Public License][]. Neo also licenses Neo4j with these extensions under closed-source commercial terms.[\[5\]][5]

Neo4j is implemented in [Java][] and accessible from software written in other languages using the [Cypher Query Language][] through a transactional HTTP endpoint, or through the binary 'bolt' protocol.[\[6\]][6][\[7\]][7][\[8\]][8][\[9\]][9]

Version 1.0 was released in February 2010.[\[10\]][10]

Neo4j version 2.0 was released in December 2013.[\[11\]][11]

In November 2016 Neo4j successfully secured $36M in Series D Funding led by Greenbridge Partners Ltd [\[12\]][12]

## Contents ##

\[hide\]

*  [1Licensing and editions][]
 *  [2Data structure][]
 *  [3Neo technology][]
 *  [4See also][]
 *  [5References][]
 *  [6Bibliography][]
 *  [7External links][]

## Licensing and editions\[[edit][]\] ##

Neo4j comes in 3 editions: Community; Enterprise; and Government. It is dual-licensed: GPLv3; and AGPLv3 / commercial. The Community Edition is free but is limited to running on 1 node only due to the lack of clustering and is without hot backups.[\[13\]][13]

The Enterprise Edition (which requires buying a license unless the application built on top of it is open-sourced) unlocks these limitations, allowing for clustering, hot backups, and monitoring. The Government Edition extends the Enterprise Edition adding additional government specific services including [FISMA][]\-related certification and accreditation support.\[*[citation needed][]*\]

## Data structure\[[edit][edit 1]\] ##

In Neo4j, everything is stored in the form of either an edge, a node, or an attribute. Each node and edge can have any number of attributes. Both the nodes and edges can be labelled. Labels can be used to narrow searches. As of version 2.0, indexing was added to Cypher with the introduction of schemas.[\[14\]][14] Previously, indexes were supported separately from Cypher.[\[15\]][15]

## Neo technology\[[edit][edit 2]\] ##

Neo4j is developed by Neo Technology, Inc., based in the [San Francisco Bay Area][], [United States][], [North America][], and also in [Malmö][Malm], [Sweden][], [Europe][]. The Neo Technology board of directors consists of Rod Johnson (founder of the [Spring Framework][]), Chris Barchak (Partner at Conor Venture Partners), Magnus Christerson (Vice President of [Intentional Software Corp][]), [Nikolaj Nyholm][] (Partner at Sunstone Capital), Guarav Tuli (Principal at Fidelity Growth Partners), and Johan Svensson (CTO of Neo Technology).[\[16\]][16]

[graph database]: https://en.wikipedia.org/wiki/Graph_database
[ACID]: https://en.wikipedia.org/wiki/ACID
[3]: https://en.wikipedia.org/wiki/Neo4j#cite_note-product-details-3
[4]: https://en.wikipedia.org/wiki/Neo4j#cite_note-DB-Engines-4
[GPL3]: https://en.wikipedia.org/wiki/GNU_General_Public_License
[open-source]: https://en.wikipedia.org/wiki/Open-source_software
[online backup]: https://en.wikipedia.org/wiki/Remote_backup_service
[high availability]: https://en.wikipedia.org/wiki/High_availability
[Affero General Public License]: https://en.wikipedia.org/wiki/Affero_General_Public_License
[5]: https://en.wikipedia.org/wiki/Neo4j#cite_note-LICENSE-5
[Java]: https://en.wikipedia.org/wiki/Java_%28programming_language%29
[Cypher Query Language]: https://en.wikipedia.org/wiki/Cypher_Query_Language
[6]: https://en.wikipedia.org/wiki/Neo4j#cite_note-bolt-6
[7]: https://en.wikipedia.org/wiki/Neo4j#cite_note-high-scalability-7
[8]: https://en.wikipedia.org/wiki/Neo4j#cite_note-InfoQ-8
[9]: https://en.wikipedia.org/wiki/Neo4j#cite_note-http-endpoint-9
[10]: https://en.wikipedia.org/wiki/Neo4j#cite_note-1.0-10
[11]: https://en.wikipedia.org/wiki/Neo4j#cite_note-11
[12]: https://en.wikipedia.org/wiki/Neo4j#cite_note-12
[1Licensing and editions]: https://en.wikipedia.org/wiki/Neo4j#Licensing_and_editions
[2Data structure]: https://en.wikipedia.org/wiki/Neo4j#Data_structure
[3Neo technology]: https://en.wikipedia.org/wiki/Neo4j#Neo_technology
[4See also]: https://en.wikipedia.org/wiki/Neo4j#See_also
[5References]: https://en.wikipedia.org/wiki/Neo4j#References
[6Bibliography]: https://en.wikipedia.org/wiki/Neo4j#Bibliography
[7External links]: https://en.wikipedia.org/wiki/Neo4j#External_links
[edit]: https://en.wikipedia.org/w/index.php?title=Neo4j&action=edit&section=1
[13]: https://en.wikipedia.org/wiki/Neo4j#cite_note-13
[FISMA]: https://en.wikipedia.org/wiki/FISMA
[citation needed]: https://en.wikipedia.org/wiki/Wikipedia:Citation_needed
[edit 1]: https://en.wikipedia.org/w/index.php?title=Neo4j&action=edit&section=2
[14]: https://en.wikipedia.org/wiki/Neo4j#cite_note-14
[15]: https://en.wikipedia.org/wiki/Neo4j#cite_note-15
[edit 2]: https://en.wikipedia.org/w/index.php?title=Neo4j&action=edit&section=3
[San Francisco Bay Area]: https://en.wikipedia.org/wiki/San_Francisco_Bay_Area
[United States]: https://en.wikipedia.org/wiki/United_States
[North America]: https://en.wikipedia.org/wiki/North_America
[Malm]: https://en.wikipedia.org/wiki/Malm%C3%B6
[Sweden]: https://en.wikipedia.org/wiki/Sweden
[Europe]: https://en.wikipedia.org/wiki/Europe
[Spring Framework]: https://en.wikipedia.org/wiki/Spring_Framework
[Intentional Software Corp]: https://en.wikipedia.org/wiki/Intentional_Software
[Nikolaj Nyholm]: https://en.wikipedia.org/wiki/Nikolaj_Nyholm
[16]: https://en.wikipedia.org/wiki/Neo4j#cite_note-staff-16