Cloudera Enterprise 5.15.x | Other versions

DROP VIEW Statement

Removes the specified view, which was originally created by the CREATE VIEW statement. Because a view is purely a logical construct (an alias for a query) with no physical data behind it, DROP VIEW only involves changes to metadata in the metastore database, not any data files in HDFS.

Syntax:

DROP VIEW [IF EXISTS] [db_name.]view_name

Statement type: DDL

Cancellation: Cannot be cancelled.

HDFS permissions: This statement does not touch any HDFS files or directories, therefore no HDFS permissions are required.

Examples:

The following example creates a series of views and then drops them. These examples illustrate how views are associated with a particular database, and both the view definitions and the view names for CREATE VIEW and DROP VIEW can refer to a view in the current database or a fully qualified view name.

-- Create and drop a view in the current database.
CREATE VIEW few_rows_from_t1 AS SELECT * FROM t1 LIMIT 10;
DROP VIEW few_rows_from_t1;

-- Create and drop a view referencing a table in a different database.
CREATE VIEW table_from_other_db AS SELECT x FROM db1.foo WHERE x IS NOT NULL;
DROP VIEW table_from_other_db;

USE db1;
-- Create a view in a different database.
CREATE VIEW db2.v1 AS SELECT * FROM db2.foo;
-- Switch into the other database and drop the view.
USE db2;
DROP VIEW v1;

USE db1;
-- Create a view in a different database.
CREATE VIEW db2.v1 AS SELECT * FROM db2.foo;
-- Drop a view in the other database.
DROP VIEW db2.v1;

Related information:

Overview of Impala Views, CREATE VIEW Statement, ALTER VIEW Statement

Page generated May 18, 2018.