ACID qualities

In electronic commerce, the four essential elements of valid processing of a transaction are (1) Atomicity: any system- or network-failure during transaction processing should result in the database reverting to the stage it was in before that transaction commenced, (2) Consistency: both the transaction-commencing stage and the transaction-concluding stage should conform to the prescribed rules for validation, otherwise the transaction is unsuccessful (aborted), (3) Isolation: each transaction should be processed independently of the other transactions being processed at the same time, (4) Durability: successful transactions should remain unaffected by any system- or network-failure.