If slightly more than an optimal number of columns are being requested in a query result (often this happens when using the model class such as DataObject as a stand-in for all of the contained columns, eg DataObject.name, DataObject.id, etc) it may be desirable to be able to exclude column names in the context of the session.query( ) method.We could do this bu prefacing a column with a minus-sign and overloading irods.column.Column __neg__), in this way for example:

sess.query(DataObject, Collection, -DataObject.collection_id, -Collection.map_id )

signifying the named columns should be removed from the query result.