While it is possible to access the database manager by clicking on a link in the login screen, there are times when that link is not available. One reason could be because the website application has been installed and the Manage Databases link is hidden from the home page.
To access the database manager directly in the default installation of Odoo, you can use the following link: http://localhost:8069/web/database/manager.
You will then be presented with the database manager screen:
Naturally, ...