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Thus, update numbers are synchronized between primaries and backups - assigned to primaries, then transferred to backups.

If all the backup nodes answered positively, then the transaction goes into the PREPARED state. In this state, it is ready for commit (COMMIT).

During commit, all transactional changes are applied to the WAL and ONLY AFTER WHAT the LWM is increased. At this point, LWM catches up with HWM.

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