1. A method of querying a database system, comprising: receiving an object query that identifies at least one entity of interest and properties, of the entity of interest, to be returned, wherein the properties are a partial set of properties of the entity; identifying tables and columns in a relational database portion of the O-R database system that correspond to the properties to be returned; obtaining data from the identified columns of the relational database portion; and returning the data from the identified columns, wherein the returned data is less than all data associated with the entity.