Server admin login of the logical server is the account that will always be able to connect to the database after provisioning.

Server admin login of the logical server is created when you provision the logical server and it acts as the server level principal with permissions to connect to and manage databases on that server. This login is the persistent administrative SQL authentication identity that you can use to access any database hosted by the logical server unless you explicitly remove or disable it.

Azure Active Directory administrator account for the server is not guaranteed to exist by default because an Azure Active Directory administrator must be explicitly configured at the server level. If it is not configured then that account will not be available to connect.

Microsoft Entra ID account that created the database does not automatically receive server admin rights. The creator of a database is not automatically granted the logical server administrator role unless that account was separately configured as the server admin or given appropriate permissions.

The traditional sa SQL account is not provided for Azure SQL Database. Microsoft does not expose a built in 'sa' account for customer use on the managed platform.

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