EFFICIENT INDEX-DATA FETCH VIA CALLBACK FOR A TABLE DATA

摘要

A callback to a data manager is earned out from an index manager in a query processing system for an index-data fetch to enable an index page held stabilized by an index manager to remain stabilized during predicate checking or data consumption operations. The ind ex manager locates a data identifier in an index and calls back to a data manager to access the data indicated by the data identifier. The data manager may carry out a predicate check or a data consuming operation on the data and if this is the case the index manager may access the next da ta identifier in the index when the data manager callback is complete. The index page need not be destabilized in such a case.