drop-column-master-key-transact-sql.md

title	DROP COLUMN MASTER KEY (Transact-SQL)
description	DROP COLUMN MASTER KEY (Transact-SQL)
author	jaszymas
ms.author	jaszymas
ms.date	10/15/2019
ms.service	sql
ms.subservice	t-sql
ms.topic	reference
f1_keywords	DROP COLUMN MASTER KEY DROP_COLUMN_MASTER_KEY_TSQL DROP COLUMN MASTER DROP_COLUMN_MASTER_TSQL
helpviewer_keywords	sys.column_master_keys catalog view
dev_langs	TSQL

DROP COLUMN MASTER KEY (Transact-SQL)

[!INCLUDE sqlserver2016-asdb-asdbmi]

Drops a column master key from a database. This is a metadata operation.

:::image type="icon" source="../../includes/media/topic-link-icon.svg" border="false"::: Transact-SQL syntax conventions

Syntax

DROP COLUMN MASTER KEY key_name;  

Arguments

key_name
The name of the column master key.

Remarks

The column master key can only be dropped if there are no column encryption key values encrypted with the column master key. To drop column encryption key values, use the DROP COLUMN ENCRYPTION KEY statement.

Permissions

Requires ALTER ANY COLUMN MASTER KEY permission on the database.

Examples

A. Dropping a column master key

The following example drops a column master key called MyCMK.

DROP COLUMN MASTER KEY MyCMK;  
GO  

See Also

CREATE COLUMN MASTER KEY (Transact-SQL)
CREATE COLUMN ENCRYPTION KEY (Transact-SQL)
DROP COLUMN ENCRYPTION KEY (Transact-SQL)
sys.column_master_keys (Transact-SQL)
Always Encrypted
Always Encrypted with secure enclaves
Overview of Key Management for Always Encrypted
Manage keys for Always Encrypted with secure enclaves