Atomicity, consistency, isolation and durability guarantee reliable updates.
ACID: Atomicity (all or nothing), Consistency (valid states), Isolation (concurrent transactions don't interfere; levels from read committed to serializable), Durability (committed data survives crashes via write-ahead logging). Locks or MVCC implement isolation.
A money transfer debits and credits within one transaction.
Transactions keep data correct when several changes must succeed or fail together, which is vital for money, orders and records.
Atomicity, consistency, isolation and durability guarantee reliable updates.
Transactions keep data correct when several changes must succeed or fail together, which is vital for money, orders and records.
Atomicity, consistency, isolation and durability, which together describe the guarantees a reliable transaction provides.
The property that concurrent transactions do not see each other's partial work, which prevents anomalies such as lost updates.
Typical applications include moving funds between two accounts so both updates happen or neither does, saving an order and its line items together and rolling back a failed batch import so the database is not left half-updated.
Study "Normalisation" first (topic 76 of 104 in Software & Computing). It covers the groundwork this topic builds on.
COMMIT and ROLLBACK. Deadlocks. Two-phase commit.
A money transfer debits and credits within one transaction.
The next topic is "Indexing", which builds directly on this one.
It is classed as Advanced in Software & Computing (topic 77 of 104). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Software & Computing.
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