What is use of hcatalog in hadoop?

hadoop hive hbase hcatalog
Vijay_Shinde picture Vijay_Shinde · Mar 20, 2014 · Viewed 31.5k times · Source

I'm new to Hadoop. I know that the HCatalog is a table and storage management layer for Hadoop. But how exactly it works and how to use it. Please give some simple example.

Answer

Prabu Soundar Rajan picture Prabu Soundar Rajan · Nov 11, 2014

In short, HCatalog opens up the hive metadata to other mapreduce tools. Every mapreduce tools has its own notion about HDFS data (example Pig sees the HDFS data as set of files, Hive sees it as tables). With having table based abstraction, HCatalog supported mapreduce tools do not need to care about where the data is stored, in which format and storage location (HBase or HDFS).

We do get the facility of WebHcat to submit jobs in an RESTful way if you configure webhcat along Hcatalog.

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