Hive Tutorial 8 : Hive Metastore

The metastore is the central repository of Hive metadata. The metastore is divided into two pieces: a service and the backing store for the data. By default, the metastore is run in the same process as the Hive service.  Using this service, it is possible to run the metastore as a standalone (remote) process. Set the METASTORE_PORT environment variable to specify the port the server will listen on.

 Types of metastore.
  • Embedded Metastore
  • Local Metastore
  • Remote Metastore

Wherever (Different Directory) we run hive query, it creates new metastore_db, please explain the reason for it?

Whenever we run the hive in embedded mode, it creates the local metastore. And

before creating the metastore it looks whether metastore already exist or not. This property is defined in configuration file hive-site.xml.

Property is “javax.jdo.option.ConnectionURL” with default value “jdbc:derby:;databaseName=metastore_db;create=true”.
So to change the behavior change the location to absolute path, so metastore will be used from that location. 

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