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HCatalog uses Hive's SerDe class to serialize and deserialize data. SerDes are provided for RCFile, CSV text, JSON text, SequenceFile and ORC formats. See Check hive documentation for updated listadditional serde that might be included in new versions.
Users can write SerDes for custom formats using the instructions at https://cwiki.apache.org/confluence/display/Hive/SerDe.
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