KILL QUERY NOTIFICATION SUBSCRIPTION (Transact-SQL)
Applies to: 
SQL Server
Azure SQL Managed Instance
Removes query notification subscriptions from the instance. This statement can remove a specific subscription or all subscriptions.
Transact-SQL syntax conventions
Syntax
KILL QUERY NOTIFICATION SUBSCRIPTION
{ ALL | subscription_id }
Arguments
ALL
Removes all subscriptions in the instance.
subscription_id
Removes the subscription with the subscription id subscription_id.
Remarks
The KILL QUERY NOTIFICATION SUBSCRIPTION statement removes query notification subscriptions without producing a notification message.
subscription_id is the id for the subscription as shown in the dynamic management view sys.dm_qn_subscriptions (Transact-SQL).
If the specified subscription id does not exist, the statement produces an error.
Permissions
Permission to execute this statement is restricted to members of the sysadmin fixed server role.
Examples
A. Removing all query notification subscriptions in the instance
The following example removes all query notification subscriptions in the instance.
KILL QUERY NOTIFICATION SUBSCRIPTION ALL ;
B. Removing a single query notification subscription
The following example removes the query notification subscription with the id 73.
KILL QUERY NOTIFICATION SUBSCRIPTION 73 ;