Configuring Hive Parameters

Parameter Description

Table 1 Hive parameter description

Parameter

Description

Default Value

hive.auto.convert.join

Whether Hive converts common join to mapjoin based on the input file size.

When Hive is used to query a join table, whatever the table size is (if the data in the join table is less than 24 MB, it is a small one), set this parameter to false. If this parameter is set to true, new mapjoin cannot be generated when you query a join table.

Possible values are as follows:

  • true

  • false

The default value is true.

hive.default.fileformat

Indicates the default file format used by Hive.

RCFile

hive.exec.reducers.max

Indicates the maximum number of reducers in a MapReduce job submitted by Hive.

999

hive.server2.thrift.max.worker.threads

Indicates the maximum number of threads that can be started in the HiveServer internal thread pool.

1,000

hive.server2.thrift.min.worker.threads

Indicates the number of threads started during initialization in the HiveServer internal thread pool.

5

hive.hbase.delete.mode.enabled

Indicates whether to enable the function of deleting HBase records from Hive. If this function is enabled, you can use remove table xx where xxx to delete HBase records from Hive.

true

hive.metastore.server.min.threads

Indicates the number of threads started by MetaStore for processing connections. If the number of threads is more than the set value, MetaStore always maintains a number of threads that is not lower than the set value, that is, the number of resident threads in the MetaStore thread pool is always higher than the set value.

200

hive.server2.enable.doAs

Indicates whether to simulate client users during sessions between HiveServer2 and other services (such as Yarn and HDFS). If you change the configuration item from false to true, users with only the column permission lose the permissions to access corresponding tables.

true