1. A live topological query method performed by a physical computing system, the method comprising: with a querying application, using a query graph to create a live topological query result from a database storing a full structure graph while not storing an entirety of said query result in a cache memory; storing a first query result portion of said query result in said cache memory, and not storing a second query result portion of said query result in said cache memory, wherein said first query result portion relates to a first node in said query graph, and said second query result portion relates to a second, different node in said query graph; in response to detecting a change within said full structure graph, performing a calculation, based on said first query result portion stored in said cache memory and said second query result portion not stored in said cache memory, to determine whether said change is relevant to said query result; notifying said querying application of a relevant change to said query result without relying on a fully cached copy of said query result; and sorting nodes of said query graph into an order of said nodes, wherein performing said calculation comprises performing calculations in an order that corresponds to said order of said nodes, wherein sorting said nodes of said query graph comprises placing said first node before said second node in said order of said nodes.
16. The method of claim 1 , wherein performing said calculations comprises: performing a first calculation to determine whether a first change relating to said first node is relevant to said first query result portion, and after performing said first calculation, performing a second calculation to determine whether a second change relating to said second node is relevant to said second query result portion.