- Atomicity
- Consistency
- Isolation
- Durability
A collection of queries that are treated as One Unite of work.
E.g. Account deposit (SELECT, UPDATE, UPDATE), more details
An atomic transaction is a transaction that will rollback all queries if one or more queries failed.
- All Queries in a transaction must succeed
- One query fails means all prior successful queries in the transaction should rollback
- If the database went down prior to a commit of a transaction all successful queries in the transaction should rollback
- Can Concurrent Transactions see changes that made by other transaction ? it depends on the configuration and the database engine impl
- Read Phenomena
- Isolation levels