Databases
Isolation level
How much concurrent transactions can see of each other: READ UNCOMMITTED, READ COMMITTED, REPEATABLE READ, SERIALIZABLE.
Why interviewers ask about it
Name the anomaly each one prevents - dirty read, non-repeatable read, phantom - rather than reciting the ladder. Knowing your database's default matters too.
Related terms
This term is part of the free Python Full-Stack interview preparation module - browse the full glossary for every definition.