A method of providing, in response to user-selected ones of attributes and/or enumerations thereof, a list of product choices from products whose compatibility is characterized by a ZDD rule model having one or more Include and Exclude ZDDs. The method comprises creating a ZDD sub-tree by scanning the Include ZDDs and keeping paths having the selected enumerations set, determining complete paths through the sub-tree to produce potentially valid combinations, checking the potentially valid combinations against the Exclude ZDDs to exclude invalid combinations, and providing resulting valid combinations. The scanning optionally includes examining nodes of the Include ZDDs or of the sub-tree against Index values of the selected enumerations to create nodes in the sub-tree. Other aspects include an apparatus implementing the method, and a computer-readable medium including program instructions enabling a processing device to perform the method.