Query execution in query processing systems

摘要

A query processing system having a data manager, and a query manager also includes a buffer. The query manager calls the data manager to access data based on a query. Where there is no predicate check or consumption operation on the record accessed, the data manager will notionally return the record to the query manager. However, the data manager accomplishes the return by writing the relevant portions of the record to a buffer. The data manager maintains stabilization of the page containing the record while the buffer is being written to. The data manager continues to access records on the stabilized page and to write such records to the buffer where appropriate. The query manager retrieves the records from the buffer after the data manager has completed its operation resulting from the query manager call.