5. The method of claim 3 wherein the collection defines a hierarchy of documents, the documents including field types that are documents of sub-fields, further comprising: computing a catalog representing a flattened arrangement of the hierarchical documents, each field of the catalog uniquely named to denote an atomic field.
3. The method of claim 1 wherein the identified type of the data values is a compound type, further comprising: recursively identifying an atomic data value resulting from decomposition of the compound type; computing a field name based on a concatenation of names of the fields of the compound type; and mapping the computed field name to a corresponding field in the DB command.