We are currently migrating our existing application to Pega Cloud. As part of the migration process, we have generated the Cloud Readiness report. During the review, we observed that several Pega-generated tables (such as history tables) do not have a primary key defined. Specifically, the report indicates that the pzinskey column is marked as NOT NULL, but there is no primary key.

We understand that adding a primary key to these tables directly would not be effective unless the corresponding class definition is also updated to reflect this change. Given that these tables are created and managed by Pega, we would like to confirm the best course of action. Should we:

1. Define a new primary key on these tables, or

2. Mark the existing pzinskey as the primary key, or

3. Leave the tables as they are, given that they are Pega-managed tables?

Could you clarify whether Pega's default handling of these tables requires any changes, or if they should be left in their current state to avoid issues during migration or after cloud migration?