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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Trivial Update of "Hive" by AshishThusoo
Date Tue, 26 Aug 2008 00:51:01 GMT
Dear Wiki user,

You have subscribed to a wiki page or wiki category on "Hadoop Wiki" for change notification.

The following page has been changed by AshishThusoo:
http://wiki.apache.org/hadoop/Hive

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  = What is 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.
  
- = What Hive is NOT =
+ = What is NOT Hive =
  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.
  
  = Status =

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