This image shows a flow chart that defines how stateless and stateful rule sessions interact with the cache in a Decision service request. First, the Oracle Business Rules Engine computes the RuleSession ID. There are two options: the RuleSession ID is in the cache or the RuleSession ID is not in the cache. If theRuleSession ID is in the cache, the Rules Engine gets the RuleSession from the cache and executes the request. If this is the final operation, the Rules Engine removes the RuleSession from the cache, returns a response, and stops. If this is not the final operation, the Rules Engine returns a response and stops. If the RuleSession ID is not in the cache, there are two options: the RuleSession is stateful or stateless. If the RuleSession is stateless, the Rules Engine gets a RuleSession from the pool, executes the request, returns the RuleSession to the pool, returns a response, and stops. If the RuleSession is stateful, the Rules Engine creates a new rule session and adds it to the cache, and executes the request. If this is the final operation, the Rules Engine removes the RuleSession from the cache, returns a response, and stops. If this is not the final operation, the Rules Engine returns a response and stops.