HCatalog is a table and storage management layer for Hadoop that enables users with different data processing tools — Pig, MapReduce — to more easily read and write data on the grid.
This is the HCatalog manual.
The old HCatalog wiki page has many other documents including additional user documentation, further information on HBase integration, and resources for contributors.
For information about the REST API for HCatalog, WebHCat (formerly Templeton), see the WebHCat Manual.
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