1. A system that facilitates cache management, comprising: a cache interface that provides a common interface for consumers that use a cache memory, the cache interface facilitates access to at least one of an HTTP (hypertext transfer protocol) cache that facilitates authentication and logon, an LPE (log predictive error) cache that facilitates caching of compiled plans for execution, a metadata cache that employs a hash table for the storage of the metadata, an XML schema cache that stores schema types, and an optimizer cache for the presentation of views of the tables; a caching component that caches selected schema components in the cache memory during schema translation to perform instance validation, the schema components are shredded into selected tables of metadata and only the most frequently used schema components are selectively loaded and cached; wherein instance validation loads only selected components of the schema components to perform the validation and during validation only the selected components that are used are loaded and cached; wherein the caching component utilizes a mechanism for cache cleanup that keeps the most frequently used schema components in memory while less frequently used schema components are removed periodically, the mechanism for cache cleanup is driven by memory pressure and based upon a number of Input/Output (I/O) reads to compute a cache entry and total memory required to compute the cache entry, such that if the system is overloaded, schema components will be more aggressively removed from the cache, and wherein the cache is not allowed to keep unused data permanently, and thus, the cache supports forced cleanup; and a costing mechanism that expresses costing in the same quantities for all caches and implements aging and cleanup, the costing mechanism is based on Central Processing Unit (CPU) and I/O time required to extract type information from the cache, and wherein lifetime of an entry in the cache is defined by usage and cost.
2. The system of claim 1 , wherein the schema structure is XML.