ACID
Atomicity, Consistency, Isolation, Durability
ELI5 — The Vibe Check
ACID is the four guarantees a reliable database makes about transactions. It is the reason you trust a bank's database with your money. If a database is ACID-compliant, your data is safe even if the server crashes mid-transaction.
Real Talk
ACID is a set of properties that guarantee reliable processing of database transactions. Atomicity ensures all operations succeed or none do. Consistency ensures the database moves from one valid state to another. Isolation ensures concurrent transactions do not interfere. Durability ensures committed data survives failures.
When You'll Hear This
"PostgreSQL is fully ACID-compliant." / "NoSQL databases often sacrifice some ACID properties for performance."
Related Terms
Atomicity
Atomicity means a transaction is all-or-nothing — like an atom that cannot be split.
Consistency
Consistency in databases means a transaction can only bring the database from one valid state to another valid state.
Durability
Durability means once the database says 'committed', your data is saved forever — even if the server crashes right after.
Isolation
Isolation means concurrent transactions do not see each other's in-progress changes.
Transaction
A transaction groups multiple database operations into one all-or-nothing bundle. Either ALL of them succeed, or NONE of them happen.