You can access your Simple Hosting database by the phpPgAdmin URL that is available down in the 'Access' section of your instances' management page:

When you click on the link to log in, you will first need to enter your Simple Hosting user number and password (the one that you specified). Then you will see the phpPgAdmin login page:

By clicking on “PostgreSQL” under “Servers” you will be taken to your login page to the database:

By default the phpPgAdmin user is hosting-db and there is no password. So just type in hosting-db as the user, leave the password empty, and click on GO.

This then brings you to the phpPgAdmin home, where you gain access to your database control panel, where you can create and manage your PostgreSQL databases.

• PostgreSQL documentation