1. A method of processing a stream of data in a database management system, in accordance with a specified query, comprising: using a scan operator, scanning a defined range of rows in a database table in accordance with the specified query, and returning qualifying rows in the defined range to a calling application; using the scan operator, suspending operation of the scanning step when there are no qualifying rows in the defined range; and automatically resuming operation of the scanning step when one or more qualifying rows in the defined range are added to the database table.