Hive Tutorial 5 : Hive Architecture


There are 3 components in Hive; a Client, Driver and Metastore. The client can be a CLI (command line interface), or an application connecting via JDBC/ODBC, which in turn goes through Thrift server, or Web based GUI like HWI (Hive Web Interface) or Hue. The Driver is made up of 3 sub-modules; Compiler, Optimizer and Executor. Hive queries get converted into Map-Reduce programs, which are then executed on Hadoop. The task of compiling and executing these jobs are carried out by the Driver. Metastore is like the namespace. It contains all the metadata of databases, tables, columns, partitions and the physical locations of the files that are part of the tables. By default Derby will be provided as metastore,we can install an external RDBMS, MySQL being the popular choice.

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