当恢复sqlserverbak文件时，原始的用户无法删除的解决方法

当你从现有的bak文件，恢复数据库时，如果数据库本身带有一个用户：比如用户叫：DemoUser.

GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Membership_BasicAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Membership_FullAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Membership_ReportingAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Profile_BasicAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Profile_FullAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Profile_ReportingAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Roles_BasicAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Roles_FullAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON ROLE::[aspnet_Roles_ReportingAccess] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON SCHEMA::[db_owner] TO [dbo] 
GO 
GO 
ALTER AUTHORIZATION ON SCHEMA::[db_owner] TO [db_owner] 
GO