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The remote_txn table records commit decisions for 2pc transactions. A successful 2pc transaction will have one row per remote connection recorded in this table. In effect it is a mapping between the distributed transaction and an identifier for each remote connection. The records are needed to protect against crashes after a frontend send a `COMMIT TRANSACTION` to one node but not all nodes involved in the transaction. Towards this end, the commitment of remote_txn rows represent a crash-safe irrevocable promise that all participating datanodes will eventually get a `COMMIT TRANSACTION` and occurs before any datanodes get a `COMMIT TRANSACTION`. The irrevocable nature of the commit of these records means that this can only happen after the system is sure all participating transactions will succeed. Thus it can only happen after all datanodes have succeeded on a `PREPARE TRANSACTION` and will happen as part of the frontend's transaction commit..