You must have a SQL connection profile created for each MS SQL Server database, OpenEdge database, and Oracle database (or any other SQL-compliant database) whose schema you want to view in DB Navigator.
DB Navigator uses SQL connection profiles to store information needed to connect to a database. Each profile contains all the information necessary to establish this connection, such as the specific JDBC driver to use and the various connection parameters required.
Before you can add a SQL connection profile, you must have a JDBC driver for the database. Typically, the driver is installed and configured automatically during installation of DB Navigator. You may, however, find that you need to configure the driver, and you can do so from the page.
Once you have the JDBC driver configured, you can create a SQL connection profile for your SQL-compliant database.