The Databases tab contains the Databases of Interest associated with the user profile. Only the Databases of Interest will be listed in the Select Database dialog when creating a new session. The databases are pulled from the currently specified data locations. Each database will display what session types can be used with it.
To limit the databases shown in the Select Database dialog, highlight the databases you do not want to see and click the Hide button. If you have a long list of databases, and you only want to see a few, you can click the Hide All button to move all of the databases to the Hidden Databases section. Then highlight the databases you want to see and click the Select button to move them back to the Databases of Interest section. You can also display a subset of the databases by making a selection in the Session Type field. Only the databases associated with the selected session type will be listed.