1. A machine-implemented method for providing aggregated analytics tracking data associated with a dynamically generated session in response to a query for analytics tracking data, the method comprising: receiving, by one or more processors, a plurality of communication including analytics tracking data corresponding to activity on one or more resources of a content publisher, each of the communication including a timestamp at which the activities occurred; storing at least part of the analytics tracking data in non-persistent storage to allow for later-received analytics tracking data to be combined the tracking data stored in the non-persistent storage; moving the analytics tracking data from the non-persistent storage to a persistent storage after a predetermined timeframe; receiving, by the one or more processors, a query for analytics tracking data corresponding to activity on the one or more resources of the content publisher, the query identifying a period of time within which the activity occurred and a client for which aggregate analytics tracking data is requested; dynamically generating, by the one or more processors, in response to the query, a temporary tracking session record specific to the query; aggregating, by the one or more processors, based on timestamps of the received communications, the analytics tracking data previously received by the one or more processors that falls within the period of time included in the query and is associated with the client for which the aggregate tracking data is requested, aggregating the analytic tracking date comprising including analytics data temporarily stored in the non-persistent storage in the aggregated analytics tracking data when the analytics data stored in the non-persistent storage includes timestamps falling within the time period included in the query and associated with the client identified in the query; associating, by the one or more processors, the aggregated analytics tracking data with the dynamically generated tracking session record; and providing the aggregated analytics tracking data associated with the dynamically generated session record in response to the query.