Error:

消息5601，级别16，状态1，第1行，由于无法在数据库 'TestNonContainedDB' 上放置锁，ALTER DATABASE 失败。请稍后再试。消息5069，级别16，状态1，第一行ALTER DATABASE 语句失败。

对应的英文信息是:Msg 5061, Level 16, State 1, Line 1 ALTER DATABASE failed because a lock could not be placed on database 'TestNonContainedDB'. Try again later. Msg 5069, Level 16, State 1, Line 1 ALTER DATABASE statement failed.

Solution:

declare @kill varchar(8000) = '';
select @kill=@kill+'kill '+convert(varchar(5),spid)+';'
from master..sysprocesses
where dbid=db_id('WSS_Content_81');
exec (@kill);