In Hive, the metastore is the central repository that stores metadata about the Hive tables, partitions, columns, and other objects. The Hive metastore can be configured to store this metadata in different types of databases, including MySQL, PostgreSQL, Oracle, and Derby.
When you create a table in Hive, the metadata about the table is stored in the metastore, and the data for the table is stored in HDFS. The location of the data in HDFS is specified using the “LOCATION” clause when you create the table. The directory where the data is stored in HDFS is known as the “Hive warehouse directory”.
The location of the Hive warehouse directory is typically specified in the Hive configuration file (hive-site.xml) using the “hive.metastore.warehouse.dir” property. By default, this property is set to “/user/hive/warehouse”, which is the directory where the data for the Hive tables is stored in HDFS.
For example, if you create a table called “sales” in Hive and specify the location of the data as “/data/sales”, the metadata about the table will be stored in the metastore, and the data for the table will be stored in the “/data/sales” directory in HDFS. The Hive warehouse directory in this case would be “/user/hive/warehouse”.
The Hive warehouse directory can be changed by modifying the value of the “hive.metastore.warehouse.dir” property in the Hive configuration file. If you change the value of this property, you must also move the existing data in the old warehouse directory to the new directory.
In summary, the Hive warehouse directory is the directory where the data for the Hive tables is stored in HDFS. The location of the Hive warehouse directory is specified in the Hive configuration file, and the default location is “/user/hive/warehouse”.