Drop SQL login even while logged in

OK, here’s the script I came up with, which worked for me. Note that you need to be a member of the processadmin server role to find and kill the connection and a member of securityadmin to drop the login. (Of course, sysadmin can do anything.)

DECLARE @loginNameToDrop sysname
SET @loginNameToDrop = '<victim login ID>';

DECLARE sessionsToKill CURSOR FAST_FORWARD FOR
    SELECT session_id
    FROM sys.dm_exec_sessions
    WHERE login_name = @loginNameToDrop
OPEN sessionsToKill

DECLARE @sessionId INT
DECLARE @statement NVARCHAR(200)

FETCH NEXT FROM sessionsToKill INTO @sessionId

WHILE @@FETCH_STATUS = 0
BEGIN
    PRINT 'Killing session ' + CAST(@sessionId AS NVARCHAR(20)) + ' for login ' + @loginNameToDrop

    SET @statement="KILL " + CAST(@sessionId AS NVARCHAR(20))
    EXEC sp_executesql @statement

    FETCH NEXT FROM sessionsToKill INTO @sessionId
END

CLOSE sessionsToKill
DEALLOCATE sessionsToKill

PRINT 'Dropping login ' + @loginNameToDrop
SET @statement="DROP LOGIN [" + @loginNameToDrop + ']'
EXEC sp_executesql @statement