Connecting your application to a database
In this application, we want to display employees' data from the HR schema on a web browser and be able to navigate between different records using buttons that help us go to the first, next, previous, and last records; employees' information should be displayed in a form-based view.
In order to retrieve employees' information, we need to establish a connection with the HR database.
In this recipe, we will use JDeveloper to establish a connection between our new ADF application and the HR schema, which comes by default with the Oracle database.
How to do it…
In order to establish a connection with the HR schema, follow the ensuing steps:
- Expand the Connect to a Database checklist item from the checklist and click on the Create a Database Connection button that will open the Create Database Connection dialog.
- Choose a connection name of your choice; I named it
HRConnectionfor clarification. - Change the username and password of the HR user to match your database's HR schema; make sure you are pointing to the right host.
- Click on the Test Connection button to make sure everything works fine, and if everything is fine, you should see a Success! message.
- Click on OK to close the dialog box.
- Mark this item as done in the checklist as well.
How it works…
When working with applications in ADF, you will need to have connections in order to establish a communication channel with different systems. One of the important connections that will be usually needed is a database connection, which establishes a connection between your application and database.
When you entered the information, you provided the connection with all the information needed in order to connect to a specific user in a specific database instance.
Your connection can be an application-based resource like the one we configured in this recipe; alternatively, it can be inside JDeveloper's resource catalog, which can be helpful if you have multiple applications that use the same database connection.
After creating a database connection, we need to create the Business Service Layer that will use the database connection.