36. A computer-readable medium containing a program which, when executed by a processor, performs a process of querying physical data logically represented by a data abstraction model, wherein the physical data being queried is contained in data structures generated from a data source having a different schema from the data structures containing the physical data being queried, the process comprising: receiving an abstract query comprising logical fields and corresponding values, wherein each of the logical fields is defined in the data abstraction model and wherein one or more of the logical fields are result fields to be returned by execution of the abstract query; and transforming, by operation of a processor, the abstract query into an executable query capable of being executed against the physical data; wherein the transforming is done using the data abstraction model and wherein the data abstraction model defines a specific path for traversing the data structures containing the physical data to reach the one or more result fields.
36. A computer-readable medium containing a program which, when executed by a processor, performs a process of querying physical data logically represented by a data abstraction model, wherein the physical data being queried is contained in data structures generated from a data source having a different schema from the data structures containing the physical data being queried, the process comprising: receiving an abstract query comprising logical fields and corresponding values, wherein each of the logical fields is defined in the data abstraction model and wherein one or more of the logical fields are result fields to be returned by execution of the abstract query; and transforming, by operation of a processor, the abstract query into an executable query capable of being executed against the physical data; wherein the transforming is done using the data abstraction model and wherein the data abstraction model defines a specific path for traversing the data structures containing the physical data to reach the one or more result fields. 40. The computer-readable medium of claim 36 , wherein the data structures containing the physical data being queried are arranged according to a relational schema.