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From Apache Wiki <wikidi...@apache.org>
Subject [Hadoop Wiki] Update of "SequenceFile" by DougCutting
Date Wed, 13 Feb 2008 17:28:50 GMT
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 DougCutting:
http://wiki.apache.org/hadoop/SequenceFile

The comment on the change is:
update for TLP move

------------------------------------------------------------------------------
  == Overview ==
  
- [http://lucene.apache.org/hadoop/docs/api/org/apache/hadoop/io/SequenceFile.html SequenceFile]
is a flat file consisting of binary key/value pairs. It is extensively used in MapReduce as
input/output formats.
+ [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/io/SequenceFile.html SequenceFile]
is a flat file consisting of binary key/value pairs. It is extensively used in MapReduce as
input/output formats.
  It is also worth noting that, internally, the temporary outputs of maps are stored using
SequenceFile.
  
  The SequenceFile provides a Writer, Reader and Sorter classes for writing, reading and sorting
respectively.
@@ -14, +14 @@

  
  The recommended way is to use the SequenceFile.createWriter methods to construct the 'preferred'
writer implementation.
  
- The [http://lucene.apache.org/hadoop/docs/api/org/apache/hadoop/io/SequenceFile.Reader.html
SequenceFile.Reader] acts as a bridge and can read any of the above SequenceFile formats.
+ The [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/io/SequenceFile.Reader.html
SequenceFile.Reader] acts as a bridge and can read any of the above SequenceFile formats.
  
  == SequenceFile Formats ==
  
@@ -31, +31 @@

   * valueClassName - String
   * compression - A boolean which specifies if ''compression'' is turned on for keys/values
in this file.
   * blockCompression -  A boolean which specifies if ''block compression'' is turned on for
keys/values in this file.
-  * compressor class - The classname of the [http://lucene.apache.org/hadoop/api/index.html?org/apache/hadoop/io/compress/CompressionCodec.html
CompressionCodec] which is used to compress/decompress keys and/or values in this !SequenceFile
(if compression is enabled).
+  * compressor class - The classname of the [http://hadoop.apache.org/core/docs/current/api/index.html?org/apache/hadoop/io/compress/CompressionCodec.html
CompressionCodec] which is used to compress/decompress keys and/or values in this !SequenceFile
(if compression is enabled).
-  * metadata - [http://lucene.apache.org/hadoop/docs/api/org/apache/hadoop/io/SequenceFile.Metadata.html
SequenceFile.Metadata] for this file (key/value pairs)
+  * metadata - [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/io/SequenceFile.Metadata.html
SequenceFile.Metadata] for this file (key/value pairs)
   * sync - A sync marker to denote end of the header.
  
- All strings are serialized using [http://lucene.apache.org/hadoop/docs/api/org/apache/hadoop/io/Text.html#writeString(java.io.DataOutput,%20java.lang.String)
Text.writeString] api.
+ All strings are serialized using [http://hadoop.apache.org/core/docs/current/api/org/apache/hadoop/io/Text.html#writeString(java.io.DataOutput,%20java.lang.String)
Text.writeString] api.
  
  [[BR]]
  [[BR]]

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