3.0 KiB
| slug | sidebar_position | sidebar_label |
|---|---|---|
| /en/sql-reference/statements/drop | 44 | DROP |
DROP Statements
Deletes existing entity. If the IF EXISTS clause is specified, these queries do not return an error if the entity does not exist. If the SYNC modifier is specified, the entity is dropped without delay.
DROP DATABASE
Deletes all tables inside the db database, then deletes the db database itself.
Syntax:
DROP DATABASE [IF EXISTS] db [ON CLUSTER cluster] [SYNC]
DROP TABLE
Deletes the table.
In case when IF EMPTY clause is specified server will check if table is empty only on replica that received initial query.
:::tip Also see UNDROP TABLE :::
Syntax:
DROP [TEMPORARY] TABLE [IF EXISTS] [IF EMPTY] [db1.]name_1[, [db2.]name_2, ...] [ON CLUSTER cluster] [SYNC]
Note that deleting multiple tables at the same time is a non-atomic deletion. If a table fails to be deleted, subsequent tables will not be deleted.
DROP DICTIONARY
Deletes the dictionary.
Syntax:
DROP DICTIONARY [IF EXISTS] [db.]name [SYNC]
DROP USER
Deletes a user.
Syntax:
DROP USER [IF EXISTS] name [,...] [ON CLUSTER cluster_name] [FROM access_storage_type]
DROP ROLE
Deletes a role. The deleted role is revoked from all the entities where it was assigned.
Syntax:
DROP ROLE [IF EXISTS] name [,...] [ON CLUSTER cluster_name] [FROM access_storage_type]
DROP ROW POLICY
Deletes a row policy. Deleted row policy is revoked from all the entities where it was assigned.
Syntax:
DROP [ROW] POLICY [IF EXISTS] name [,...] ON [database.]table [,...] [ON CLUSTER cluster_name] [FROM access_storage_type]
DROP QUOTA
Deletes a quota. The deleted quota is revoked from all the entities where it was assigned.
Syntax:
DROP QUOTA [IF EXISTS] name [,...] [ON CLUSTER cluster_name] [FROM access_storage_type]
DROP SETTINGS PROFILE
Deletes a settings profile. The deleted settings profile is revoked from all the entities where it was assigned.
Syntax:
DROP [SETTINGS] PROFILE [IF EXISTS] name [,...] [ON CLUSTER cluster_name] [FROM access_storage_type]
DROP VIEW
Deletes a view. Views can be deleted by a DROP TABLE command as well but DROP VIEW checks that [db.]name is a view.
Syntax:
DROP VIEW [IF EXISTS] [db.]name [ON CLUSTER cluster] [SYNC]
DROP FUNCTION
Deletes a user defined function created by CREATE FUNCTION. System functions can not be dropped.
Syntax
DROP FUNCTION [IF EXISTS] function_name [on CLUSTER cluster]
Example
CREATE FUNCTION linear_equation AS (x, k, b) -> k*x + b;
DROP FUNCTION linear_equation;
DROP NAMED COLLECTION
Deletes a named collection.
Syntax
DROP NAMED COLLECTION [IF EXISTS] name [on CLUSTER cluster]
Example
CREATE NAMED COLLECTION foobar AS a = '1', b = '2';
DROP NAMED COLLECTION foobar;