Editing Isolation (database systems) (section)

{{Short description|Database transaction integrity concept}}
{{Refimprove|date=January 2009}}
In [[database]] systems, '''isolation''' is one of the [[ACID]] (''[[Atomicity (database systems)|Atomicity]], [[Consistency (database systems)|Consistency]], Isolation, [[Durability (database systems)|Durability]]'') [[database transaction|transaction]] properties. It determines how [[Database transaction|transaction]] integrity is visible to other users and systems. A lower isolation level increases the ability of many users to access the same data at the same time, but also increases the number of [[Concurrency (computer science)|concurrency]] effects (such as [[Write–read conflict | dirty reads]] or [[lost update]]s) users might encounter. Conversely, a higher isolation level reduces the types of concurrency effects that users may encounter, but requires more system resources and increases the chances that one transaction will block another.<ref>"Isolation Levels in the Database Engine", TechNet, Microsoft, https://technet.microsoft.com/en-us/library/ms189122(v=SQL.105).aspx</ref>