Consistency and currency in functional databases

We consider a hybrid model of databases, in which a functional component T is defined as an extension to an imperative component B. T. is loosely coupled to B through a highly parallel function network N. which provides a simple failsafe test of whether an existing assignment of values to a given view (subset) T' of T is consistent. If this test fails, or when a "current" view of T' is desired, N can be requested to "refresh" T' so that its values become consistent with respect to the current assignment to B. These requests are serviced by N without danger of system deadlock.