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]]
