Publisher Summary Fast invalidation is a key point for enabling dynamic content caching while maintaining cached web pages fresh. Various applications, including e-commerce sites, on the other hand, do not require the caches to reflect all the data in the database, yet they require that all outdated pages in the caches be invalidated in a timely fashion. In today's multi-tiered application architectures, clients do not access data stored in the databases directly. Instead, they use applications that, in turn, invoke the DBMS to generate the relevant content. Since executing application programs may require significant time and other resources, it is more advantageous to cache application results in a result cache. Various view materialization and update management techniques have been proposed to deal with updates to the underlying data. These techniques guarantee that the cached results are always consistent with the underlying data. Several applications, including e-commerce sites, on the other hand, do not require the caches be consistent all the time.