1. A computer storage medium having computer-executable instructions, which when executed perform actions, comprising: receiving a data access request from an application that has objects that conform to an object model of the application, the object model comprising a collection of objects through which the application is able to examine and manipulate application data; based at least in part on an expression that associates a behavior of an object that conforms to the object model to at least one operation associated with an abstract data model, mapping the data access request into a set of one or more operations that operate on the abstract data model, the abstract data model indicating how data is represented and accessed from a data store; and providing the one or more operations to a data access component to access data corresponding to the request from the data store.