数据库中，限制用户只能访问一个数据库

USE master;
GO
--Step 1: (create a new user)
create LOGIN hello WITH PASSWORD="foo", CHECK_POLICY = OFF;


-- Step 2:(deny view to any database)
USE master;
GO
DENY VIEW ANY DATABASE TO hello; 


 -- step 3 (then authorized the user for that specific database , you have to use the  master by doing use master as below)
USE master;
GO
ALTER AUTHORIZATION ON DATABASE::yourDB TO hello;
GO

https://stackoverflow.com/questions/4085700/restrict-sql-server-login-access-to-only-one-database