Software → Databases
Transaction
A unit of database work that groups operations into a consistent commit or rollback boundary.
Where it fits
A transaction groups database operations into a unit of work. It is essential for preserving correctness when multiple reads/writes must succeed or fail together.
Mental model
A transaction creates a boundary: either the intended set of changes is committed, or the database rolls them back.
Example
Moving money between accounts should debit one account and credit another in one transaction. Half-completed transfers are unacceptable.
Common mistakes
- Holding transactions open too long.
- Assuming all isolation levels behave the same.
- Forgetting that distributed transactions are much harder than local ones.
Related concepts
ACID, isolation level, write-ahead log, concurrency control, database.