The description on persistable data objects in RHDM document [1] may be misleading (give users a misunderstanding) as if we can persist such objects for rule use cases, though persistence feature is actually not supported in RHDM (for rule use cases). So as to avoid such misleading, the description [1] should be corrected appropriately, e.g. add note that persistence feature is not supported for rule use cases, or remove the description of the step 4 (to make a data object persistable).

[1] Red Hat Decision Manager > 7.11 > Developing decision services in Red Hat Decision Manager - 17.1. Creating data objects
https://access.redhat.com/documentation/en-us/red_hat_decision_manager/7.11/html-single/developing_decision_services_in_red_hat_decision_manager/index#data-objects-create-proc_drl-rules

4. To make your data object persistable, select the Persistable checkbox. Persistable data objects are able to be stored in a database according to the JPA specification. The default JPA is Hibernate.