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From Xiaobo Gu <guxiaobo1...@gmail.com>
Subject File format question when write map-reduce applications
Date Wed, 06 Jul 2011 10:03:19 GMT
Does every block of files in HDFS have to be the same file format when
writing map-reduce applications, a more specific question is , when
dealing with CSV files, can we have a head in the file? I have seen
Mahout applications using the UCI repository file format which is
similar as CSV without header, does it because all map reduce task
must run semantically, having a header will cause one map task be
unique to others.


Xiaobo Gu

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