1. A system for providing a virtual item set representing a subset of items stored within an original data structure, comprising: a virtual item set processor configured to generate a plurality of virtual items that are a subset of items in the original data structure; and a virtual item set including the plurality of virtual items, each virtual item including a data field containing a data item from the original data structure, and a metadata field, the meta field data including position information representing the position of the data field within an original data structure.