Is there a specific reason why the primary keys are so important to preserve?
Without knowing your reason why, then I can suggest the following
- DBA Route. There are quite a few options available to you at DBA level such as taking backups/restoring etc or even crudely using checkindent (t-sql) to reseed the col. identity value. But these should only be undertaken by people that know what they are doing at database level.
- Low-code Route. Create a standalone app (with its own entities) that you use specifically for performance testing. That way you can continue to use it for testing in production without polluting an entity with test data.
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