ClickHouse/docs/en/sql-reference/statements/drop.md

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---
sidebar_position: 44
sidebar_label: DROP
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---
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# DROP Statements
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Deletes existing entity. If the `IF EXISTS` clause is specified, these queries do not return an error if the entity does not exist.
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## DROP DATABASE
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Deletes all tables inside the `db` database, then deletes the `db` database itself.
Syntax:
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``` sql
DROP DATABASE [IF EXISTS] db [ON CLUSTER cluster]
```
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## DROP TABLE
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Deletes the table.
Syntax:
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``` sql
DROP [TEMPORARY] TABLE [IF EXISTS] [db.]name [ON CLUSTER cluster]
```
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## DROP DICTIONARY
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Deletes the dictionary.
Syntax:
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``` sql
DROP DICTIONARY [IF EXISTS] [db.]name
```
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## DROP USER
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Deletes a user.
Syntax:
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``` sql
DROP USER [IF EXISTS] name [,...] [ON CLUSTER cluster_name]
```
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## DROP ROLE
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Deletes a role. The deleted role is revoked from all the entities where it was assigned.
Syntax:
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``` sql
DROP ROLE [IF EXISTS] name [,...] [ON CLUSTER cluster_name]
```
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## DROP ROW POLICY
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Deletes a row policy. Deleted row policy is revoked from all the entities where it was assigned.
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Syntax:
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``` sql
DROP [ROW] POLICY [IF EXISTS] name [,...] ON [database.]table [,...] [ON CLUSTER cluster_name]
```
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## DROP QUOTA
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Deletes a quota. The deleted quota is revoked from all the entities where it was assigned.
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Syntax:
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``` sql
DROP QUOTA [IF EXISTS] name [,...] [ON CLUSTER cluster_name]
```
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## DROP SETTINGS PROFILE
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Deletes a settings profile. The deleted settings profile is revoked from all the entities where it was assigned.
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Syntax:
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``` sql
DROP [SETTINGS] PROFILE [IF EXISTS] name [,...] [ON CLUSTER cluster_name]
```
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## DROP VIEW
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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:
``` sql
DROP VIEW [IF EXISTS] [db.]name [ON CLUSTER cluster]
```
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## DROP FUNCTION
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Deletes a user defined function created by [CREATE FUNCTION](./create/function.md).
System functions can not be dropped.
**Syntax**
``` sql
DROP FUNCTION [IF EXISTS] function_name
```
**Example**
``` sql
CREATE FUNCTION linear_equation AS (x, k, b) -> k*x + b;
DROP FUNCTION linear_equation;
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```