This document describes the Hive user configuration properties sometimes called parameters, variables, or options , and notes which releases introduced new properties. The canonical list of configuration properties is managed in the HiveConf Java class, so refer to the HiveConf. For information about how to use these configuration properties, see. That document also describes administrative configuration properties for setting up Hive in the section. As of Hive 0. Query and DDL Execution hive. Options are: mr Map Reduce, default , tez execution, for Hadoop 2 only , or spark execution, for Hive 1. While mr remains the default engine for historical reasons, it is itself a historical engine and is deprecated in the Hive 2 line. It may be removed without further warning. See and for more information, and see the and the below for their configuration properties. Typically set to a prime close to the number of available hosts. Hadoop set this to 1 by default, whereas Hive uses -1 as its default value. By setting this property to -1, Hive will automatically figure out what should be the number of reducers. The default in Hive 0. If the one specified in the configuration property is negative, Hive will use this as the maximum number of reducers when automatically determining the number of reducers. They can be renewed added, removed, or updated by executing the without having to restart HiveServer2. These jars can be used just like the auxiliary classes in for creating UDFs or SerDes. When running Hive in local mode, see. This can lead to explosion across the map-reduce boundary if the cardinality of T is very high, and map-side aggregation does not do a very good job. This parameter decides if Hive should add an additional map-reduce job. If the memory usage is higher than this number, force to flush data. Set to 1 to make sure hash aggregation is never turned off. This configuration property was removed in release 0. This configuration property was removed in release 0. Note: See for more configuration properties related to Hive indexes. Note: Turn on as well to use file format specific indexes with PPD. If this config is true, only pushed down filters remain in the operator tree, and the original filter is removed. If this config is false, the original filter is also left in the operator tree at the original place. If the local task's memory usage is more than this number, the local task will be aborted. It means the data of small table is too large to be held in memory. If the local task's memory usage is more than this number, the local task will abort by itself. It mean
