A data page (formerly called a declare page) rule defines the contents of a clipboard page.
Data pages are only created when first accessed and do not persist. They are not saved to the PegaRULES database, and are reconstructed when next accessed and the previous version is expired.
There are two types of data pages:
Almost all rule types can reference data page rules and provide values for the properties on such pages because they do not explicitly reference the rule.
When a requestor accesses a data page, the data page creates a new instance of itself on the clipboard. Each data page and each instance of it on the clipboard have a name that starts with Declare_ or D_.
Rules of any type that can reference properties on pages other than the current or primary page, including activities, decisions, and parse rules, can reference properties on data pages in a read-only context. When a non-existent property is referenced, the data page creates the property in read-only mode.
Use the Data Explorer to list all data pages that are available to your application.
Click Designer Studio > Data Model > Clipboard Pages > Data Pages to list data pages used by the current application. See Data Model category — Clipboard Pages page.
Data pages are instances of the Rule-Declare-Pages class and are part of the Data Model category.