mapreduce的二次排序 SecondarySort

关于二次排序主要涉及到这么几个东西:

0.20.0 以前使用的是

setPartitionerClass

setOutputkeyComparatorClass

setOutputValueGroupingComparator

0.20.0以后使用是

job.setPartitionerClass(Partitioner p);

job.setSortComparatorClass(RawComparator c);

job.setGroupingComparatorClass(RawComparator c);

 

http://www.cnblogs.com/xuxm2007/archive/2011/09/03/2165805.html

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