What is Hadoop WebHCat?

WebHCat is the REST API for HCatalog, a table and storage management layer for Hadoop. Using WebHCat. Installation. Configuration. Reference.

What is WebHCat server cloudera?

WebHCat is a web API for HCatalog and related Hadoop components.

What is HCatalog used for?

The goal of HCatalog is to allow Pig and MapReduce to be able to use the same data structures as Hive. Then there is no need to convert data. The first shows that all three products use Hadoop to store data. Hive stores its metadata (i.e., schema) in MySQL or Derby.

How do I start Hive in local mode?

Starting with release 0.7, Hive fully supports local mode execution. To enable this, the user can enable the following option: hive> SET mapreduce.framework.name=local; In addition, mapred.

How do I access HCatalog?

HCatalog Command Line Interface (CLI) can be invoked from the command $HIVE_HOME/HCatalog/bin/hcat where $HIVE_HOME is the home directory of Hive. hcat is a command used to initialize the HCatalog server.

What is hive Hcat?

HCatalog is a table storage management tool for Hadoop that exposes the tabular data of Hive metastore to other Hadoop applications. It enables users with different data processing tools (Pig, MapReduce) to easily write data onto a grid.

Is a HCatalog REST API?

This document describes HCatalog REST API. As shown in the figure below, developers make HTTP requests to access Hadoop MapReduce, Pig, Hive, and HCatalog DDL from within applications. Data and code used by this API is maintained in HDFS.

What is HCatalog and the Metastore?

HCatalog is a tool that allows you to access Hive metastore tables within Pig, Spark SQL, and/or custom MapReduce applications. HCatalog has a REST interface and command line client that allows you to create tables or do other operations. You then write your applications to access the tables using HCatalog libraries.

Is Hadoop required for hive?

Hive provided JDBC driver to query hive like JDBC, however if you are planning to run Hive queries on production system, you need Hadoop infrastructure to be available. Hive queries eventually converts into map-reduce jobs and HDFS is used as data storage for Hive tables.

What type of SQL does hive use?

HiveQL
Hive was created to allow non-programmers familiar with SQL to work with petabytes of data, using a SQL-like interface called HiveQL. Traditional relational databases are designed for interactive queries on small to medium datasets and do not process huge datasets well.

What is webhcat Hadoop?

WebHCat ( (or Templeton) service is a REST operation based API for HCatalog . WebHCat provides a service that you can use to run Hadoop MapReduce (or YARN), Pig, Hive jobs or perform Hive metadata operations using an HTTP (REST style) interface.

How is data maintained in webhcat?

Data and code used by this API are maintained in HDFS. HCatalog DDL commands are executed directly when requested. MapReduce, Pig, and Hive jobs are placed in queue by WebHCat (Templeton) servers and can be monitored for progress or stopped as required.

What is hcatalog and webhcat?

The HCatalog project graduated from the Apache incubator and merged with the Hive project on March 26, 2013. Hive version 0.11.0 is the first release that includes HCatalog and its REST API, WebHCat. This document describes the HCatalog REST API, WebHCat, which was previously called Templeton.

What is Templeton webhcat?

WebHCat ( (or Templeton) service is a REST operation based API for HCatalog . WebHCat provides a service that you can use to run Hadoop MapReduce (or YARN), Pig, Hive jobs or perform Hive metadata operations using an HTTP (REST style) interface. WebHCat is a REST interface for remote job execution, such as: