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The following page has been changed by ZhengShao: http://wiki.apache.org/hadoop/Hive ------------------------------------------------------------------------------ = Welcome to the Hive Wiki! = - - For more information, please see the official [http://hadoop.apache.org/hive/ Hive website]. - - = Information = - Following are some useful links for users and developers interested in Hive: - * [wiki:/GettingStarted Getting Started Guide] - * [wiki:/UserGuide Information for Users] - * [wiki:/LanguageManual HiveQL Language Manual] - * [wiki:/AdminManual Administrator Manual] - * [wiki:/Tutorial Hive Tutorial] - * [wiki:/HiveWebInterface Hive Web Interface] - * [wiki:/HiveJDBCInterface Hive JDBC Interface] - * [wiki:/Design Design Document] - * [wiki:/DeveloperGuide Information for Developers] - * [wiki:/Roadmap Roadmap/call to Add More Features] - * [wiki:/Performance Hive Performance] - * [wiki:/HiveAws Hive on Amazon Web Services] - * [wiki:/Presentations Presentations About Hive] - * [wiki:/PoweredBy A List of Sites and Applications Powered by Hive] - * [wiki:/FAQ Frequently Asked Questions on IRC/mailing list] = What is Hive = [http://hadoop.apache.org/hive/ Hive] is a data warehouse infrastructure built on top of Hadoop that provides tools to enable easy data summarization, adhoc querying and analysis of large datasets data stored in Hadoop files. It provides a mechanism to put structure on this data and it also provides a simple query language called QL which is based on SQL and which enables users familiar with SQL to query this data. At the same time, this language also allows traditional map/reduce programmers to be able to plug in their custom mappers and reducers to do more sophisticated analysis which may not be supported by the built in capabilities of the language. + + Hive does not mandate read or written data be in "hive format" - there is no such thing; Hive works equally well on Thrift, control delimited, or your data format. Please see File Format and SerDe in Developer Guide for details. = What Hive is NOT = Hive is based on Hadoop which is a batch processing system. Accordingly, this system does not and cannot promise low latencies on queries. The paradigm here is strictly of submitting jobs and being notified when the jobs are completed as opposed to real time queries. As a result it should not be compared with systems like Oracle where analysis is done on a significantly smaller amount of data but the analysis proceeds much more iteratively with the response times between iterations being less than a few minutes. For Hive queries response times for even the smallest jobs can be of the order of 5-10 minutes and for larger jobs this may even run into hours. If your input data is small you can execute a query in a short time. For example, if a table has 100 rows you can 'set mapred.reduce.tasks=1' and 'set mapred.map.tasks=1' and the query time will be ~15 seconds. - Hive does not mandate read or written data be in "hive format" - there is no such thing; Hive works equally well on Thrift, control delimited, or your data format. + = Information = + Following are some useful links for users and developers interested in Hive: + * General information about Hive + * [wiki:/GettingStarted Getting Started] + * [wiki:/Presentations Presentations About Hive] + * [wiki:/PoweredBy A List of Sites and Applications Powered by Hive] + * [wiki:/FAQ Frequently Asked Questions on IRC/mailing list] + * [http://hadoop.apache.org/hive/mailing_lists.html#Users hive-users mailing list] + * Hive IRC Channel: ##hive at irc.freenode.net + * For users: + * [wiki:/UserGuide Hive User Guide] + * [wiki:/Tutorial Hive Tutorial] + * [wiki:/LanguageManual HiveQL Language Manual] + * [wiki:/HiveWebInterface Hive Web Interface] + * [wiki:/HiveJDBCInterface Hive JDBC Interface] + * For developers: + * [wiki:/HowToContribute How to Contribute] + * [wiki:/DeveloperGuide Hive Developer Guide] + * [wiki:/Performance Hive Performance] + * [wiki:/Design Hive Design Document] + * [wiki:/Roadmap Roadmap/call to Add More Features] + * For administrators: + * [wiki:/AdminManual Administrator Manual] + * [wiki:/HiveAws Hive on Amazon Web Services] + * Build Status: + * [http://hudson.zones.apache.org/hudson/view/Hive/ Hive builds] + * [wiki:/HudsonBuild HudsonBuild] - = Get Involved = + For more information, please see the official [http://hadoop.apache.org/hive/ Hive website]. - [wiki:/HowToContribute HowToContribute] - - [http://hudson.zones.apache.org/hudson/view/Hive/ Hive builds] - - [http://hadoop.apache.org/hive/mailing_lists.html#Users hive-users mailing list] - - [wiki:/HudsonBuild HudsonBuild] - - Hive IRC Channel: ##hive at irc.freenode.net -
