DROP ROLE Statement (CDH 5.2 or higher only)
The DROP ROLE statement removes a role from the metastore database. Once dropped, the role is revoked for all users to whom it was previously assigned, and all privileges granted to that role are revoked. Queries that are already executing are not affected. Impala verifies the role information approximately every 60 seconds, so the effects of DROP ROLE might not take effect for new Impala queries for a brief period.
DROP ROLE role_name
Only administrative users (initially, a predefined set of users specified in the Sentry service configuration file) can use this statement.
Impala makes use of any roles and privileges specified by the GRANT and REVOKE statements in Hive, and Hive makes use of any roles and privileges specified by the GRANT and REVOKE statements in Impala. The Impala GRANT and REVOKE statements for privileges do not require the ROLE keyword to be repeated before each role name, unlike the equivalent Hive statements.
Cancellation: Cannot be cancelled.
HDFS permissions: This statement does not touch any HDFS files or directories, therefore no HDFS permissions are required.