Abstract: A system and method for maintaining large-grained database concurrency with a log monitor incorporating dynamically redefinable business logic are described. Operations expressed in a data manipulation language are executed against a source database. At least one operation constitutes a commit operation that completes each database transaction. A current rule set is defined. Each rule includes business logic specifying a data selection criteria for records stored in the source database. A log entry is periodically generated in a log for each transaction committed to the source database. Each log entry identifies an affected record and includes transactional data. The transaction identified in each log entry is evaluated against the data selection criteria specified in the current rule set. A new record is built in accordance with metadata describing a destination database. The new record contains select transactional data from the log entry of each transaction meeting the selection criteria.

Abstract: A general purpose application interaction protocol, referred to herein as the Commerce Exchange Interaction Protocol (CXIP), governs the exchange of data between applications resident in computers in a distributed network such as the Internet, providing for application interoperability. CXIP enables process communications among network-distributed software applications, particularly, but not exclusively, among software applications having dissimilar platforms, language dependencies or vendor dependencies. Data structures, object and method invocation requests are exchanged between applications by means of XML documents based on CXIP semantics. The application interaction protocol, which is not specific to any particular functional domain and specifies interactions that are independent of transactional content, includes four component parts: message formats, message types, exchange semantics and transportation assumptions.

Abstract: A method and apparatus for implementing stack extensions in a modifier stack that is associated with a plurality of components that are sequentially applied to a geometry object when the modifier stack is evaluated. According to one aspect of the invention, an extension channel object is attached to the geometry object. The extension channel object is associated with a notification mechanism that notifies the extension channel object if a particular event occurs while the modifier stack is being evaluating. In response to receiving a notification that one of the plurality of components has caused a particular event to occur while the modifier stack is being evaluated, the extension channel object influences how the geometry object is modified by the component within the modifier stack.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: Approaches for determining the actual physical topology of network devices in a network are disclosed. To determine a physical topology, a discovery mechanism determines a set of network addresses for identifying devices within a network. Based on the set of network addresses, the discovery mechanism identifies a group of devices that are associated with the network. Layer 2 and Layer 3 configuration information is gathered from the group of devices to identify possible neighboring devices within the network. The configuration information is then processed to generate topology information that identifies true neighboring devices and the actual links that exist between each of the neighboring devices. The approaches eliminate misleading information and prevent generation of incorrect topologies.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A method and system are described for generating railing objects that model railing structures, such as fences. According to the method, a railing object is generated along a path within a design layout. As rendered, the railing object includes posts and railings, with the option of using filling material between the posts. According to one variation, the railing object substantially follows an existing path. The railing object may comprise an increasing number of segments to better follow the curvature of the path. Any modification applied to the path is automatically applied to the railing object after the railing object is applied to the path. That is, every railing object component (e.g. post, railing, fencing) will be repositioned along the new position of the path. A mechanism is provided for automatically applying the modifications to the geometric dimensions of a single component instance of a railing object to every instance of that component on the railing object.

Abstract: An aggregate index is used for accessing an aggregate value associated with one or more rows of a database table. The aggregate values are stored in the index entries of the index, thus allowing determination of aggregate values without accessing the underlying database table. The aggregate index is created by determining an aggregate value associated with an index entry, and storing the aggregate value with the index entry. The aggregate value is determined by accessing information corresponding to the index entry and processing the information. In the case of an index entry in the form of a branch node, the information might be aggregate values from other nodes, or values of items in the database pointed to by the index entries that are leaf nodes. The aggregate values may be stored in index entries of any type of index.

Abstract: A method and apparatus are provided for verifying policies that govern a policy-based system. The method and apparatus may be implemented as a policy verifier that acts upon one or more policies. Each policy comprises a condition and a consequent. The policy verifier acquires configuration information about the system under management, thereby acquiring an understanding of the system. The policy verifier determines whether all the policies are feasible for the system, and if not, reports problems or errors that cause the policies to be non-feasible. The policy verifier also verifies that a configuration required by a particular policy consequent can be actually carried out by the managed system. In one embodiment, the policy verifier operates on network management policies, of a policy-based network management system. As a result, the invention improves the accuracy and safety of policies prepared for a network that previously did not use policy-based management.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A mechanism for determining the actual physical topology of network devices in a network is disclosed. To determine a physical topology, a discovery mechanism determines a set of network addresses for identifying devices within a network. Based on the set of network addresses, the discovery mechanism identifies a group of devices that are associated with the network. Layer 2 and Layer 3 configuration information is gathered from the group of devices to identify possible neighboring devices within the network. The configuration information is then processed to generate topology information that identifies true neighboring devices and the actual links that exist between each of the neighboring devices. The mechanism eliminates misleading information and prevents generation of incorrect topologies.

Abstract: A method and apparatus are provided for transferring a resource from the cache of one database server to the cache of another database server without first writing the resource to disk. When a database server (Requestor) desires to modify a resource, the Requestor asks for the current version of the resource. The database server that has the current version (Holder) directly ships the current version to the Requestor. Upon shipping the version, the Holder loses permission to modify the resource, but continues to retain the resource in memory. When the retained version of the resource, or a later version thereof, is written to disk, the Holder can discard the retained version of the resource. Otherwise, the Holder does not discard the retained version. Using this technique, single-server failures are recovered without having to merge the recovery logs of the various database servers that had access to the resource.

Abstract: A system is provided for handling an error by identifying an activity that generated the error. The system determines whether the activity has an associated user-defined error handling process. If the activity has an associated user-defined error handling process, then the system executes the associated user-defined error handling process. If the activity does not have an associated user-defined error handling process, then the system executes a default error handling process. A particular activity my have multiple associated user-defined error handling processes. The system selects among the multiple user-defined error handling processes using one or more error handling parameters. The system includes an activity execution module configured to execute process definitions and identify errors that occur when executing process definitions.

Abstract: A method and apparatus are provided for recognizing and processing conflicts in policies that govern a policy-based system. The method and apparatus may be implemented as a policy verifier that acts upon one or more policies. Each policy is formally defined and comprises a condition and a consequent, each of which are further formally defined in terms of component elements. A conflict among two or more policies is formally defined to occur when the condition of a first policy and the condition of a second policy may be simultaneously true, and when the consequent of the first policy and the consequent of the second policy may not be carried out simultaneously. When a policy conflict is detected, the conflict is resolved by bringing it to the attention of a user or external system, and receiving information that corrects one of the policies or specifies a precedence relationship among the policies.

Abstract: A database or some portion thereof is partitioned into ownership groups. Each ownership group is assigned one or more database servers as owners of the ownership group. The database servers that are assigned as owners of an ownership group are treated as the owners of all data items that belong to the ownership group. That is, they are allowed to directly access the data items within the ownership group, while other database servers are not allowed to directly access those data items. Accordingly, a database system is provided which includes one or more persistent storage devices having a database stored thereon, and a plurality of database servers executing on a plurality of nodes. Each node has direct access to the persistent storage devices. At least a portion of the database is partitioned into a plurality of ownership groups. Each ownership group is assigned an owner set.

Abstract: A reliable connectionless protocol is used in a networking environment. A transport layer receives data for transfer between a source node and a destination node on a network. The transport layer divides the data into predetermined length data packets, and generates a segment header for each data packet. The transport layer generates independent segments by combining each data packet with a corresponding segment header. Consequently, each segment, including the first segment and the last segment, contains a data packet. The independent segments are transferred from the source node to the destination node via the network without establishing a connection. A transport layer on the destination node creates local state upon receipt of the first segment, and extracts the data from the data packets to re-construct the original data. The local state is released when the destination node receives the last segment in the message.

Abstract: A method and apparatus are provided for verifying policies that govern a policy-based system. The method and apparatus may be implemented as a policy verifier that acts upon one or more policies. Each policy comprises a condition and a consequent. The policy verifier acquires configuration information about the system under management, thereby acquiring an understanding of the system. The policy verifier determines whether all the policies can be satisfied by the system, and if not, reports problems or errors in the policies that cause the policies to be non-satisfiable. The policy verifier determines whether all the policies are feasible for the system, and if not, reports problems or errors that cause the policies to be non-feasible. The policy verifier also verifies that a configuration required by a particular policy consequent can be actually carried out by the managed system. In one embodiment, the policy verifier operates on network management policies, of a policy-based network management system.