Choosing Between a Sandbox Schema and a Restricted Role for Safe PL/SQL Testing in SQL Developer

Goal: Determine which method—creating a dedicated sandbox schema or using a restricted database role—provides reliable isolation for PL/SQL integration tests in SQL Developer while avoiding the use of production credentials.

Constraints: A sandbox schema needs extra storage and periodic refresh to stay current, whereas a role‑based approach depends on correctly designed privileges and ongoing role maintenance. An unresolved behavior in SQL Developer 21.2+ is that the Test Connection dialog does not automatically enforce role‑based restrictions when the role is granted through a proxy user, showing full privileges despite the role limit and creating inconsistent visibility during ad‑hoc testing.

Which approach offers more consistent privilege enforcement when proxy users are involved? How does the Test Connection dialog inconsistency affect confidence in role‑based testing? What level of operational overhead (storage refresh vs role maintenance) is acceptable for your team?