1. A data processing system for acquiring a data element from a data control system and performing data processing on the data element, the data control system categorizing a plurality of data elements into a plurality of clusters and storing the plurality of clusters, comprising: a cache unit for acquiring from the data control system a data element belonging to a single cluster of the plurality of clusters, and cluster update information of which a data value is changed when any data element belonging to the single cluster is updated, and for caching the data element and the cluster update information thus acquired; a group-of-clusters update information acquisition unit for acquiring, from the data control system, group-of-clusters update information which is computed by the data control system based on two or more pieces of the cluster update information stored in the data control system with respect to two or more of the clusters containing two or more of the data elements having been cached, the group-of-clusters update information pertaining to a group of clusters consisting of the two or more clusters; a group-of-clusters update information computation unit for computing the group-of-clusters update information with respect to the group of clusters based on the two or more pieces of cluster update information having been cached; and an update judging unit for judging that an aforementioned data element thus cached belonging to an aforementioned cluster of the group of clusters is the most updated one in a condition where the group-of-clusters update information which is computed by the group-of-clusters update information computation unit coincides with the group-of-clusters update information which is acquired from the data control system.