A few more information requests if you don't mind. Can you analyze the table ie "ANALYZE USERS" without error? Could you please paste the output from "\d+ users". And try SELECT COUNT(*) FROM users WHERE id_usr IS NULL; Is your database large? Can you shut down the instance cleanly and take a backup of it before making any further changes?Could you also copy the mailing list into your reply please to ensure others can see and possibly assist?
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Соглашаюсь с условиями обработки персональных данных