One embodiment includes receiving user input specifying a plurality of result fields for an abstract query. Each result field corresponds to a logical field specification of a data abstraction model abstractly describing the data in the database. The method further includes receiving user input selecting one of the plurality of result fields, and receiving user input specifying a classification definition for the selected result field. The classification definition is suitable for dividing data to be returned for the selected result field into a plurality of categories. Then, a classification field for the abstract query is generated on the basis of the selected result field and the classification definition. The classification field is included with the abstract query. The method further includes receiving a user request for execution of the abstract query against the database.