System for modifying persistent database based upon set of data elements formed after selective insertion or deletion

摘要

A system and method for dynamic processing of unbounded data streams. The system is adapted to operate on a data processing system including a display panel and a database stored on a non-volatile storage device. An input stream of data elements is received by the system from the database. The input stream of data elements is designated as a source data stream. An insert list of data elements is provided to maintain a first set of data elements arranged in sequence according to a corresponding sequence value; the first set of data elements is not contained in the source data stream. A delete list of data elements is provided to maintain a second set of data elements presently in the source data stream, and arranged in sequence according to a corresponding sequence value. A flagged list of data elements selected for further processing by a user, contains a third list of data elements arranged in sequence according to a corresponding sequence. In order to identify a data element to be returned to the display panel in response to a request for a current element in an apparent list of data elements, the system filters the source data stream through the insert list of data elements to obtain a candidate data element for the next element in the apparent list. The system then filters candidate data element through the delete list of data elements to verify that the candidate element has not been deleted. The system may optionally check the candidate data element through the flagged list of data elements to determine if the candidate element has been flagged. Finally, the system sets the candidate data element as the current data element in the apparent list and returns the current data element to the display panel.