Meaning
Database management systems use strict design rules to ensure that data remains accurate and reliable during execution. This transactional integrity prevents data corruption by ensuring that either all parts of a multi-step operation succeed or the entire operation is cancelled. It governs payment processing, inventory updates, and user registration systems.
It stops applying once the database state is successfully committed to permanent storage.
State Consistency
Information storage systems must maintain correct values across all tables at all times. State consistency ensures that any change to the database adheres to all predefined rules, such as foreign key constraints and unique field requirements. If a transaction violates these rules, the system rejects the entire operation.
This prevention maintains database health and reliability.
Execution Assurance
System software relies on structured locks to prevent multiple processes from modifying the same data simultaneously. Execution assurance is the mechanism that prevents conflicts by isolating active transactions from each other. It ensures that each transaction is processed as if it were the only operation running.
This isolation prevents data overwrites and incorrect balances.
Failure Recovery
Hardware failures and network disconnects can interrupt transactions before they are completed. The failure recovery protocol is the automated routine that runs when a system crashes mid-transaction. For example, if a bank transfer requires deducting one hundred dollars from Account A and adding it to Account B, and the server crashes after the deduction but before the addition, the system restarts and reads the transaction log.
It then rolls back the deduction to restore Account A to its original state. This rollback action ensures that funds do not vanish during a system failure, maintaining the trust of the institution’s customers.
