Hi ,

Decision data records offer a flexible mechanism for the type of input values that require frequent changes without having to adjust the strategy. Changes to the values of decision data records become directly available when you update the rule. Decision data records can provide a simple list of values (typically, this is the case with global control parameters), or a set of values that are available in a specific context (for example, proposition parameters and channel centric parameters). The values of decision data records are typically defined by business users through the Decision Manager portal, but this functionality is not tied to the facilities in the portal and can be used in Designer Studio as well. The content of decision data records is defined by the extension points that system architects use to configure the data model and user interface supporting decision data.

You can refer : https://community.pega.com/sites/default/files/help_v74/procomhelpmain.htm#rule-/rule-decision-/rule-decision-decisionparameters/main.htm

The versioned propositions are listed in the Hierarchy tab of the Proposition Management landing page, under the Decision data records section. These propositions are part of the decision data rule instance managing propositions for a given group. They are also referred to as decision data records.

The unversioned propositions listed in the Unversioned proposition data tab of the Proposition Management landing page are data instances of the group data class.