The ApplicationOntology object (described in ) enables you to write queries that use the unique object identifiers of topics without having to write your own lookup and caching code. By using a single ApplicationOntology object for your application you can make use of the efficient caching of topic identifiers and you can write your queries without having to include sub-queries to find ontology-related topics. Use the ReplaceReferences() method of the ApplicationOntology class to replace cache key references with topic identifiers in your query strings