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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "HadoopMapReduce" by DanielTunkelang
Date Thu, 09 Jul 2009 04:10:58 GMT
Dear Wiki user,

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The following page has been changed by DanielTunkelang:
http://wiki.apache.org/hadoop/HadoopMapReduce

The comment on the change is:
fixed broken link to TextInputFormat class

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  writer per configured reduce task. It will then proceed to read
  its !FileSplit using the [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapred/RecordReader.html
RecordReader] it gets from the specified
  [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapreduce/InputFormat.html
InputFormat]. !InputFormat parses the input and generates
- key-value pairs. !InputFormat must also handle records that may be split on the !FileSplit
boundary. For example [http://svn.apache.org/viewcvs.cgi/hadoop/core/trunk/src/mapred/org/apache/hadoop/mapred/TextInputFormat.java?view=markup
TextInputFormat] will read the last line of the !FileSplit past the split boundary and, when
reading other than the first !FileSplit, !TextInputFormat ignores the content up to the first
newline.
+ key-value pairs. !InputFormat must also handle records that may be split on the !FileSplit
boundary. For example [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/mapreduce/lib/input/TextInputFormat.html
TextInputFormat] will read the last line of the !FileSplit past the split boundary and, when
reading other than the first !FileSplit, !TextInputFormat ignores the content up to the first
newline.
  
  It is not necessary for the !InputFormat to
  generate both meaningful keys ''and'' values. For example the

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