drop-asymmetric-key-transact-sql.md

title	DROP ASYMMETRIC KEY (Transact-SQL) | Microsoft Docs
ms.custom
ms.date	03/06/2017
ms.prod	sql
ms.prod_service	database-engine, sql-database
ms.reviewer
ms.technology	t-sql
ms.topic	language-reference
f1_keywords	DROP ASYMMETRIC KEY DROP_ASYMMETRIC_KEY_TSQL
dev_langs	TSQL
helpviewer_keywords	asymmetric keys [SQL Server], removing removing asymmetric keys encryption [SQL Server], asymmetric keys DROP ASYMMETRIC KEY statement dropping asymmetric keys deleting asymmetric keys cryptography [SQL Server], asymmetric keys
ms.assetid	bf94ac07-9b62-4318-b55b-1eed8f3a1ac6
author	VanMSFT
ms.author	vanto

DROP ASYMMETRIC KEY (Transact-SQL)

[!INCLUDE SQL Server SQL Database]

Removes an asymmetric key from the database.

Transact-SQL Syntax Conventions

Syntax

  
DROP ASYMMETRIC KEY key_name [ REMOVE PROVIDER KEY ]  

Arguments

key_name
Is the name of the asymmetric key to be dropped from the database.

REMOVE PROVIDER KEY
Removes an Extensible Key Management (EKM) key from an EKM device. For more information about Extensible Key Management, see Extensible Key Management (EKM).

Remarks

An asymmetric key with which a symmetric key in the database has been encrypted, or to which a user or login is mapped, cannot be dropped. Before you drop such a key, you must drop any user or login that is mapped to the key. You must also drop or change any symmetric key encrypted with the asymmetric key. You can use the DROP ENCRYPTION option of ALTER SYMMETRIC KEY to remove encryption by an asymmetric key.

Metadata of asymmetric keys can be accessed by using the sys.asymmetric_keys catalog view. The keys themselves cannot be directly viewed from inside the database.

If the asymmetric key is mapped to an Extensible Key Management (EKM) key on an EKM device and the REMOVE PROVIDER KEY option is not specified, the key will be dropped from the database but not the device. A warning will be issued.

Permissions

Requires CONTROL permission on the asymmetric key.

Examples

The following example removes the asymmetric key MirandaXAsymKey6 from the AdventureWorks2012 database.

USE AdventureWorks2012;  
DROP ASYMMETRIC KEY MirandaXAsymKey6;  

See Also

CREATE ASYMMETRIC KEY (Transact-SQL)
ALTER ASYMMETRIC KEY (Transact-SQL)
Encryption Hierarchy
ALTER SYMMETRIC KEY (Transact-SQL)