# Overview Snapshot isolation is a #flashcard form of weak isolation where every transaction reads from a consistent snapshot of the database. In other words, each transaction works off a version of the database that includes all committed data at the point where the transaction started. *Readers never block writers, and writers never block readers.* <!--ID: 1751507776820--> # Key Considerations To track all the versions of the database when running multiple transaction as the same time, many databases use [[Multi-version Concurrency Control (MVCC)]]. # Pros - Especially useful for read-only transactions # Cons # Use Cases # Related Topics - [[Repeatable Read]]