should trigger the table to be considered volatile until the transaction is completed. Often, cache engines will only invalidate a result before or after the query is executed. Distributed caches w/ lack of communication: If a cache design is using an underlying storage layer, when used as a distributed cache, invalidations are done locally, based on what tables are written to at a given time. Unfortunately, other nodes may have written cache objects for the same table, and these objects won't be invalidated. When used for local session data with upstream client persistence, this may be acceptable, but for shared data that needs to maintain consistency across sessions, this can cause data consistency problems. References External links Middle-Tier Database Caching for e-Business fa:حافظه_پنهان_پایگاه_داده