Abstract: A method and system for optimizing the passing of a parameter to a routine is provided. It is determined if any parameters are aliased in a call to a called routine. In the absence of aliases, calling routines passing parameters to called routines using “call by reference”. Recovery mechanisms are provided, when appropriate, when unhandled exception occur during execution of the called routines. According to the method, a recovery mechanism includes encapsulating the called routine and call statement block with a “catch-all” exception handler. The response to an otherwise unhandled exception includes restoring the actual parameter using a stored copy of the actual parameter. The restoration is performed by making a handle point to the copy of the actual parameter that was made before execution of the called routine.

Abstract: A method and apparatus are provided for retrieving data from a table in a database. According to the method one or more indexes arc generated for use in processing a query by selecting values as unique key values from one or more columns in a table in a relational database system. Each unique key corresponds to a row in the table. The condition of whether a row in a table satisfies a search criterion, is represented by a bit in a bitstring or, in cases where the bitstring is segmented, in a segment of bitstring. The unique keys and corresponding segment of bitstring are then stored in an index.

Abstract: A method and apparatus for managing access to a resource using anticipatory lock conversions in a distributed lock management system is provided. According to the method, when an entity requests a lock on a resource, the entity is granted, if possible, a lock with a more restrictive lock mode than is required if it is determined that the entity may require the more restrictive lock mode in the near future.

Abstract: A method and apparatus are provided for implementing a content based publish-and-subscribe system in a relational database system. A subscriber may request for messages by using a query language supported by the database server. The queries are then used as subscription rules for determining whether an incoming message is to be sent to the subscriber. Evaluation of incoming messages against subscription rules involves a two-tier process. The first tier involves filtering out all the subscription rules that could not possibly apply to the incoming message. The second tier involves further evaluation of the incoming message, if needed, to determine which subscribers are to receive the incoming message. In another aspect of the embodiment, in cases where the publisher is the relational database system itself, queries that request for messages are not stored as subscription rules because publication of the messages is implicit.

Abstract: Techniques are described for reducing the number of sort operations required for a query that contains window functions. The techniques involves determining a set of Partition By and Order By clause pairs that corresponds to the set of window functions and then grouping the Partition By and Order By clause pairs into Ordering Groups where each Ordering Group may be satisfied by a single sort operation. From the set of Ordering Groups, a minimal set of Ordering Groups is determined. The techniques account for the interaction of orderings from Group By and Order By clauses in the query block.

Abstract: A method and apparatus for notifying a first network node that a second network node has gone off-line during a communication session is disclosed. The first network node may be a client and the second network node may be a server. The client and the server communicate using an embedded protocol, such as telnet. The protocol defines a login process that must be used by the client to establish a logical connection to the server. The protocol also specifies that the server must immediately issue a response to a login attempt, by either establishing a connection or issuing an error message. The first network node determines that no communications have been received from the second server in a pre-determined period of time. The first network node generates invalid login information, such as a randomly generated invalid user id and an invalid password. A login command is sent from the first network node to the second network node. The login command includes the previously generated invalid login information.

Abstract: A grounding clip for computer peripheral cards includes a base and at least one finger. The base has a contact surface and contains an aperture. Further, the aperture is sized to receive the particular peripheral card that must be discharged by the grounding clip. The finger extends from an internal length portion of the base, and in the case where a plurality of fingers are provided, they paired and disposed in registry along opposing internal length portions of the base. Each finger includes a discharge surface for contacting and grounding the peripheral card.