Although it’s been mentioned in other papers and presentations, it’s worth emphasizing the differences between object fetch and the DQL query call.

A Fetch call would retrieve all attribute information of an object from server, this information will then be cached on the client side. A DQL query such as: select object_name, r_content_size from dm_document where r_object_id = ‘123456789' will only retrieve the attributes specified in the select statement of the query.

A dm_document object has around 70 attributes. If you are only interested in several attributes of an object you should use a DQL statement to avoid retrieving unnecessary information, this becomes significant especially in a low bandwidth environment. Fetch should used when most attributes of an object are wanted, and/or that attribute information is repeatedly needed in multiple places.

Note that a DFC getObject() call is effectively a fetch call, you should avoid creating a idfsysobject with dfsession.getObject() just to look at a couple attributes of the object, use query.execute(iDfSession, DFCLib.IDfQuery_DF_READ_QUERY) and specify the attributes of interest in the select statement of the query instead.