CREATE Statements #
With Hive dialect, the following DROP statements are supported for now:
- DROP DATABASE
- DROP TABLE
- DROP VIEW
- DROP MARCO
- DROP FUNCTION
DROP DATABASE #
Description #
DROP DATABASE
statement is used to drop a database as well as the tables/directories associated with the database.
Syntax #
DROP (DATABASE|SCHEMA) [IF EXISTS] database_name [RESTRICT|CASCADE];
The use of SCHEMA
and DATABASE
are interchangeable - they mean the same thing.
The default behavior is RESTRICT
, where DROP DATABASE
will fail if the database is not empty.
To drop the tables in the database as well, use DROP DATABASE ... CASCADE
.
DROP
returns an error if the database doesn’t exist, unless IF EXISTS
is specified
or the configuration variable hive.exec.drop.ignorenonexistent
is set to true.
Examples #
DROP DATABASE db1 CASCADE;
DROP TABLE #
Description #
DROP TABLE
statement removes metadata and data for this table.
The data is actually moved to the .Trash/Current
directory if Trash is configured.
The metadata is completely lost.
When drop an EXTERNAL
table, data in the table will not be deleted from the filesystem.
Syntax #
DROP TABLE [IF EXISTS] table_name;
DROP
returns an error if the table doesn’t exist, unless IF EXISTS
is specified
or the configuration variable hive.exec.drop.ignorenonexistent
is set to true.
Examples #
DROP TABLE IF EXISTS t1;
DROP VIEW #
Description #
DROP VIEW
statement is used to removed metadata for the specified view.
Syntax #
DROP VIEW [IF EXISTS] [db_name.]view_name;
DROP
returns an error if the view doesn’t exist, unless IF EXISTS
is specified
or the configuration variable hive.exec.drop.ignorenonexistent
is set to true.
Examples #
DROP VIEW IF EXISTS v1;
DROP MARCO #
DROP MARCO
statement is used to drop the existing MARCO
.
Please refer to CREATE MARCO for how to create MARCO
.
Syntax #
DROP TEMPORARY MACRO [IF EXISTS] macro_name;
DROP
returns an error if the macro doesn’t exist, unless IF EXISTS
is specified.
Examples #
DROP TEMPORARY MACRO IF EXISTS m1;
DROP FUNCTION #
DROP FUNCTION
statement is used to drop the existing FUNCTION
.
Syntax #
--- Drop temporary function
DROP TEMPORARY FUNCTION [IF EXISTS] function_name;
--- Drop permanent function
DROP FUNCTION [IF EXISTS] function_name;
DROP
returns an error if the function doesn’t exist, unless IF EXISTS
is specified
or the configuration variable hive.exec.drop.ignorenonexistent
is set to true.
Examples #
DROP FUNCTION IF EXISTS f1;