Abstract: A method and apparatus are provided for extending the behavior and attributes of applications designed using a fourth generation language (4GL) programming tool. Specifically, a 4GL programming tool is provided that allows application designers to specify the implementation classes of the components that are used in the applications that they design using the 4GL programming tool. The implementation classes thus specified may define attributes and behaviors not supported by the corresponding component implementations provided with the 4GL programming tool. During runtime, methods in the specified implementation classes are invoked. To correctly invoke the methods of user-specified implementation classes, the interfaces of the methods must be known to the entity performing the invocations.

Abstract: A method and mechanism are provided for accessing data. Values are stored for a set of context attributes associated with a session between a database user and a database server. The database system includes an attribute setting mechanism that selectively restricts access to the set of context attributes based on a policy. During the session, the database server executes a query that contains a reference to one or more of the context attributes. For example, the query may contain a predicate that requires a comparison between a context attribute value and a constant. The database server processes the query based on current values of the one or more of the context attributes referenced in the query. A mechanism is also provided for dynamically attaching predicates to queries, where the predicates are attached based on a policy. For example, the database system detects that a query is issued against a database object.

Abstract: Techniques are provided for executing distinct aggregation operations in a manner that is more scalable and efficient than prior techniques. A three-stage technique is provided to parallelize aggregation operations that involve both grouping and multiple distinct-key columns. Such queries are handled by splitting rows into as many pieces as there are distinct aggregates in the query, and processing the row pieces. During the first-stage, a set of slave processes scans the rows of the base tables and performs partial duplicate elimination. During the second-stage, a set of slave processes completes the duplicate elimination and performs partial set function aggregation. During the third-stage, a third set of slave processes completes the set aggregation to produce the results of the distinct aggregation operation.

Abstract: A power supply switching apparatus for a facsimile machine includes a power supply switch, a switch controller and a capacitor-based power supply. The power supply switch is configured to selectively couple and decouple a power supply to a facsimile machine. The switch controller is communicatively coupled to the power supply switch and is configured to control the power supply switch in response to the satisfaction of one or more switch criteria. The capacitor-based power supply is communicatively coupled to and provides power to the power supply switch, for example, when the power supply switching apparatus is operating in a standby mode, or any other time the switch controller needs power. Other embodiments include the use of a second power supply to recharge the capacitor-based switch power supply and a switch trigger instead of a switch controller.

Abstract: A method and apparatus are provided for locating buried objects prior to digging at a current location. According to the invention, a positioning device is taken to the location where digging is to take place. The positioning device receives positioning signals from one or more positioning stations, and based upon the positioning signals, determines the current location of the positioning device and hence the location of the dig site. Once the current location is determined, a registry database containing the locations of previously buried objects is accessed. The registry database is queried for all locations within a selected distance of the current location which have buried objects. If this query returns no records, then it is probably safe to dig at the current location. On the other hand, if the query returns one or more locations, then further digging at the current location should either be avoided or performed with great caution.