Unless it is a contained database, we must create a login for connecting with SQL Server in order to access a database. Databases are accessed using Users and Users are created using Logins. Is it same with Azure SQL Databases? Should I create a login before creating a user?
With Azure SQL Database, it is not a must as Azure SQL database is a contained database (portable). We can create a user account with a password for accessing the database without creating a login. However, it allows us to create a login in the master and then create a user in our database using the login created in the master.
What if I created a user in my database using a login?
The main advantage is maintenance. If the login needs to be dropped or disabled, it can be simply done in the master database. Not only that, since multiple user accounts can be created with multiple databases using the same login, one login can be used for connecting the multiple databases.
The biggest disadvantage with this is, database becomes non-portable. If databases needs to be copied, moved or replicated, login must be created with new servers.
What if I created a user in my database without creating a login?
The main benefit we get is a portable database. Since all users with passwords are maintained inside the database, it can be copied, moved, replicated without any issue.
However, if the environment has multiple databases and users need to access more than one database, then multiple user accounts have to be created.