hbase需要使用mapreduce来查询吗
hbase本身已经提供了实时查询功能了,如bloom filters等.如果加入mr的话,那么好处是什么呢?
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如果使用mr对hbase中的数据进行非实时性的统计分析,这是可行的,但这样已经有了替代方案:hive.
这正如pig基于hadoop一样,将mr的业务抽取出来了.
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references:
http://hadoop.nchc.org.tw/phpbb/viewtopic.php?f=7&t=2320
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用MR(MapReduce)查询hbase数据－用到TableMapper和Scan hbase doc:HBase provides:
Linear and modular scalability.Strictly consistent reads and writes.Automatic and configurable sharding of tablesAutomatic failover support between RegionServers.Convenient base classes for backing Hadoop MapReduce jobs with HBase tables.Easy to use Java API for client access.Block cache and Bloom Filters for real-time queries.Query predicate push down via server side FiltersThrift gateway and a REST-ful Web service that supports XML, Protobuf, and binary data encoding optionsExtensible jruby-based (JIRB) shellSupport for exporting metrics via the Hadoop metrics subsystem to files or Ganglia; or via JMX?
