3.1 Understanding Applications

An Oracle APEX application is an HTML interface that exists on top of database objects such as tables or procedures.

About Applications

An application is a collection of pages linked together using navigation menus, tabs, buttons, or hypertext links. Application pages share a common session state and authentication.

To create an application, a developer runs the Create Application Wizard to declaratively assemble pages and navigation. Individual pages are organized using containers called regions. Regions can contain text, custom PL/SQL, reports, charts, maps, calendars, web service content, or forms. Forms are made up of fields (called items) which can be selected from the multitude of built-in types (such as text fields, text areas, radio groups, select lists, checkboxes, date pickers, and popup list of values).

Developers can also create their own custom item types using plug-ins. Session state (or application context) is transparently managed and the user interface presentation is separated from the application logic enabling developers to manage the look and feel of an application by simply selecting a different theme.

About Application Pages

A page is the basic building block of an application. Every application consists of one or multiple pages. Each page can have buttons and fields (called items) which are grouped into containers called regions. Pages can include application logic (or processes). You can branch from one page to the next using conditional navigation; perform calculations (called computations); perform validations (such as edit checks); and display reports, calendars, and charts. You view and edit a page in Page Designer.

About Data Sources and Source Types

You can edit page components in Page Designer. The Source section in Page Designer prompts you to specify a Data Source and then a Source Type. The Data Source determines where database objects reside: for example, in a local database or a remote database using REST Enabled SQL Service or REST Data Source. The Source Type determines how the data is retrieved. Available Source Types include:

  • Table / View - The data is retrieved based on a table or view. All columns of that table or view are selected. Provide the name of the table or view to use.
  • SQL Query - The data is retrieved based on a SQL Query. Provide the SQL Query to be executed.
  • Function Body returning SQL Query - The data is retrieved based on the SQL Query returned by executing a Function Body. Provide a PL/SQL or JavaScript (MLE) block returning a SQL Query. APEX will then execute that SQL query.
  • Property Graph - Available for local database on Oracle Database 23ai or later. The data is retrieved based on a Property Graph.