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 EvgenyRyabitskiy: New page: = Table of Contents = * [#intro Introduction] * [#datamodel Data Model] * [#conceptual Conceptual View] * [#physical Physical Storage View] * [#arch Architecture and Implementation] * [#master HBaseMaster] * [#hregion HRegionServer] * [#client HBase Client] [[Anchor(intro)]] = Introduction = This paper is HBase oriented analogue of Google [ Bigtable paper]. This paper will be self-sufficient. It's created on 06.03.09 and now is in progress.... HBase is an [ Apache] open source project whose goal is to provide Bigtable-like storage for the Hadoop Distributed Computing Environment. HBase leverages the distributed data storage provided by the [ Hadoop Distributed File System (HDFS)]. Data is logically organized into tables, rows and columns. An iterator-like interface is available for scanning through a row range and, of course, there is the ability to retrieve a column value for a specific row key. Any particular column may have multiple versions for the same row key. [[Anchor(datamodel)]] = Data Model = HBase uses a data model very similar to that of Bigtable. Applications store data rows in labeled tables. A data row has a sortable row key and an arbitrary number of columns. The table is stored sparsely, so that rows in the same table can have widely varying numbers of columns. A column name has the form ''":