first-committer-wins-on-write-conflict

Status: IN

When two concurrent transactions write the same key, the first to call `commit()` succeeds and the second is aborted automatically

Source: entries/2026/05/29/topic-mvcc-snapshot-isolation.md

Example

for key in tx.write_set:
    for other_id in self._committed:
        other = self._transactions[other_id]
        if key in other.write_set and other.tx_id > tx.start_timestamp:
            tx._status = "aborted"
            return False  # first committer wins

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