Consistency (database systems)

<p>In <a href="/facts/Database_systems/VYcpkevb">database systems</a>, consistency (or correctness) refers to the requirement that any given <a href="/facts/Database_transaction/q1Etrsl8">database transaction</a> must change affected data only in allowed ways. Any data written to the database must be valid according to all defined rules, including <a href="/facts/Integrity_constraints/g3XGbKIH">constraints</a>, <a href="/facts/Cascading_rollback/HNtToVYw">cascades</a>, <a href="/facts/Database_trigger/yhI7KW6H">triggers</a>, and any combination thereof.  This does not guarantee correctness of the transaction in all ways the application programmer might have wanted (that is the responsibility of application-level code) but merely that any programming errors cannot result in the violation of any defined database constraints.
</p><p>In a distributed system, referencing <a href="/facts/CAP_theorem/qnxvcbLp">CAP theorem</a>, consistency can also be understood as after a successful write, update or delete of a Record, any read request immediately receives the latest value of the Record.
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Consistency (database systems) open-in-new

Consistency (database systems)