1. A system comprising: a processor; a storage device; a database held in the storage device; two or more data access objects stored in a memory and operable on the processor, wherein one or more data access objects comprise: exclusive access privileges to a subset of data within the database, and one or more of a read method that provides access to data and a write method that causes data to be stored; a proxy object stored in the memory and operable on the processor to access data via data access object methods, and the proxy object includes a valuate method, the execution of which occurs upon a data access object action in regard to the first data access object and causes data to be passed from a second data access object to the proxy object, wherein the proxy object processes the second data access object data to derive a data result and store the derived data result in the first data access object via a write method of the first data access object; and wherein: at least one data object under control of one of the data access objects is a derived data object as a function of one or more other data objects, the derived data object including a lock object including lock source data and a validity indicator, and the proxy object is operable to update the validity indicator upon an update to a data object from which the derived data object is derived.