Does ArcGIS support SQL Server partially contained databases?

Yes. Partially contained databases in SQL Server are isolated from other databases and from the SQL Server instance. ArcGIS supports connections to databases configured with partial containment and allows enterprise geodatabase functionality in this database configuration.

Connecting to a partially contained database

When connecting to a partially contained database using the Database Connection dialog box in ArcGIS Pro, type the database name in the Database text box.  A contained database user does not have an associated SQL Server login, and is unable to retrieve the list of databases from the SQL Server instance to populate the Database drop-down list.

Partial containment implies that some server dependencies still exist. For instance, traditional database users that are mapped to SQL Server logins can coexist with new contained database users in the same database. During the login process, SQL Server must determine the type of authentication used for each connection.

Connecting with SQL Server Authentication first attempts database-level authentication if a partially contained database is specified in the connection string. If a matching contained user is not found, then authentication falls back to the server level and looks for a matching login. If a database is NOT specified in the connection string, then server-level authentication is attempted first.

Creating contained database users

Creating contained database users must be accomplished using database management system (DBMS) tools. This type of user is not mapped to a SQL Server login and the password hash is stored in the user database. The Create Database User tool always creates database users with associated SQL Server logins, so you cannot use it to create contained database users. Note that before you create a geodatabase in the database, you must create the geodatabase administrator user with DBMS tools too.

Creating a geodatabase in a contained database

Before you create an enterprise geodatabase in a contained database, you must use DBMS tools to create the database.  To partially contain a database, the Containment Type must be set to Partial. Once a partially contained database has been created, run the Enable Enterprise Geodatabase geoprocessing tool to create the geodatabase system tables, stored procedures, views and functions in the new database.

Note:
See the Microsoft SQL Server documentation for more information about creating partially contained databases, and creating contained database users.