How to create contained database users

• These instructions apply to SQL 2012 and later.
• Log in to the SQL server using SQL Server Management Studio using your primary SQL DB user.
•  Create a new query and run this SQL command against your database:

use master
go
alter database [Database Name]
set single_user with rollback immediate
go
alter database [Database Name]
set CONTAINMENT  = PARTIAL
go
alter database [Database Name]
set multi_user
go

• Go to the Security folder under your database.
• Right click on the Security folder and choose "New User..."
• Choose "SQL user with a password" for the User Type.
• Enter the password to this contained DB User.
• On the "Select a page" column, click "Membership."
• Click db_owner.