1. A method of providing a logical framework for defining abstract operations for accessing physical data comprising a plurality of physical entities each comprising a plurality of physical fields, the method comprising: providing an abstract model for defining abstract operation specifications logically describing operations to access the data, the abstract model comprising: (a) a plurality of logical fields; (b) a mapping rule for each of the plurality of logical fields, which map each of the plurality of logical fields to at least one of the physical entities of the data; and (c) a plurality of model entity definitions, each comprising at least one logical field corresponding to a physical entity; providing an interface from which each of the plurality of model entity definitions is selectable in generating an abstract operation specification to access the data of the physical entity corresponding to a selected model entity definition; and providing a run-time component to transform, according to the abstract model, the abstract operation specifications into physical operation specifications consistent with the physical data.