database migration questions

Hello cz.nic Team I have a few questions related to database migration of FRED if you don't mind. ==== When trying to download the latest sources from https://fred.nic.cz/page/2904/download/#source I've realised, that they're not available. E.g. the latest migration scripts are available in fred-db*deb, but the tarball is not a corresponding one. Could you please try to release latest sources in tarballs? ==== I've noticed, that upgrade to 2.19.0 creates a table object_state_backup. However, beside DDL from 2.18.0-2.19.0.sql I don't see this table being used anywhere else. Can it be deleted? ==== Could you briefly describe what's the purpose of tables: contact_address contact_address_history As far I can tell after analysing the sources, these tables are populated by a functionality called from MojeID ( =your special NIC registrar to keep domain contacts defined at central level, not each registrar's level). ==== What are the following tables for? Or: How the checks of contacts are working? Is is something related to checking if a contact's address fields are valid? contact_check contact_check_history contact_check_message_map contact_check_object_state_request_map contact_check_poll_message_map contact_test_result contact_test_result_history contact_testsuite_map enum_contact_check_status enum_contact_check_status_localization enum_contact_test enum_contact_test_localization enum_contact_test_status enum_contact_test_status_localization enum_contact_testsuite enum_contact_testsuite_localization ==== There's a table notification_queue. I can't find any usage of it (maybe because not all tarballs are up to date). What is it for? Do you replicate this table using Slony? (Because it has neither primary nor unique key.) Best regards Piotr