Abstract: A method and apparatus for replicating data between heterogeneous databases is provided. Data is replicated between two heterogeneous databases with the use of a volatile storage queue, enabling the rapid replication of data across databases provided by different vendors or operating on different platforms. According to one embodiment, an in-memory queue is used to queue change operations to be performed on a target data repository. The change operations may be operations that were applied to a source data repository. An apply process retrieves the change operations from in-memory queue and commits the change operations to persistent storage. When the change operations have been committed, the apply process notifies the source platform that the particular change operation has been stored.

Abstract: A computer is programmed to parse a network that interconnects databases in a distributed database system, into a number of paths, wherein each path starts in a source database that is a source of changes and ends in a destination database that uses the changes to replicate the source database. The computer identifies databases that occur within each path in the network, and queries the identified databases to obtain statistics for each path. Statistics along each path are analyzed automatically, to identify a component in each path as a candidate for further investigation. The identified component may be marked as a bottleneck e.g. if there are no other paths connected to it. Alternatively the identified component may be a source of changes for another path that has a bottleneck or that has another candidate for further investigation. The identified bottleneck is displayed to the user with recommendations for improvement.

Abstract: Described herein are various approaches that allow rules to be used to specify actions, that alleviate the complexity and burden of developing and maintaining rules in a rules-based messaging system, and that provide more efficient ways of evaluating rules. The approaches allow rules to specify user-defined transformation functions for transforming messages, to specify when and how to perform row migration, and to specify other types of actions. Rules are grouped into rule sets. Several types of rule sets, referred to as positive and negative rule sets, allow users to use rules that are less complex to develop and maintain. Rule sets are evaluated more efficiently by attempting to evaluate the rule set with less information than is needed to evaluate all the rules in the rule set. Also, the results of rules evaluations that are based on a set of values are cached for later retrieval.

Abstract: To export source tablespaces, an auxiliary database system is created and started with a minimum configuration. Copies of versions of the source tablespaces are restored from database backups to the auxiliary database system. A copy of a version of a tablespace is referred to herein as a tablespace instance. The tablespace instances restored from database backups are recovered to a particular point-in-time. A script is then generated. The script can be executed by a database server of the destination database to import the tablespace instances.

Abstract: In some messaging system architectures, messages can cycle back to the originator of a message, who may then propagate the message, causing the cycle to be repeated. Described herein are techniques that use rules and fields in a redo log, to manage message flows such that undesired cycles are prevented. The techniques may be used in messaging systems that have various topologies.

Abstract: In accordance with an embodiment of the present invention, a heterogeneous data sharing mechanism comprising a capture process and an apply process may be provided in a database system. The capture process mines or receives, at the source entity, a plurality of records that belong to a plurality of transactions. Here, first records from a first transaction in the plurality of transactions are interleaved with one or more records from one or more different transactions in the plurality of transactions. The capture process orders the plurality of records into a stream of ordered records such that all records that belong to a transaction are stored contiguously in a single block of records in the stream. Subsequently, the capture process sends the stream of ordered records from the source entity to the sink entity. Alternatively, the apply process retrieves the stream of ordered records from the capture process.

Abstract: An approach is provided to automatically resolve conflict between instantiation and ongoing data replication operations. In an embodiment, incremental change records that describe one or more database operations are received at a sink entity. Here, all of the one or more database operations have occurred in a second database after a particular time. A first database operation in the one or more database operations to a particular row in the first database is applied. When a conflict with a second database operation that operates on the particular row is detected, one or more compensating actions, which may, but are not limited to, be a different database operation and/or an operation that creates a conflict log entry, may be performed. Here, the second database operation has occurred in the second database prior to the particular time. When the second database operation is to be performed, an appropriate operation may be performed.

Abstract: A source database system sends information to a destination database system, and each database system generates a separate set of sequence information. A mapping is maintained between the two sets of sequence information. Using the mapping, the destination database system may be used to restore changes lost at the source database system without reinstating the source database. Additionally, queries associated with a particular point in a sequence associated with the sequence information of the source database may be redirected to the destination database, and the destination database system may serve as a logical standby for the source database system. A variety of methods of maintaining and/or extracting the mapping information are disclosed.

Abstract: Splitting and merging database object information sharing streams. Streams are also referred to herein as “propagations”. Splitting and merging information sharing streams can be used to improve performance in a information sharing environment when a failed or slow DBS impacts the performance. In one embodiment, an auto split process monitors the progress of applying changes at each node and detects the presence of a failed or a slow node. Once the failed or slow node is identified, the auto split process splits the propagation such that the offending node is sent through a separate propagation. Furthermore, an auto merge process can be started to monitor the newly created separate propagation. At a later point, the new propagation can be merged back into the original stream. For example, if the offending node catches up with other nodes, the auto merge process merges the newly created propagation back to the original propagation.

Abstract: A checkpoint free log mining mechanism comprising a capture process and an apply process that are logically associated with each other may be provided in a database system. In an embodiment, log mining information published by the capture process to the apply process comprises a complete set of log information for each interesting transaction. A system change number of a start transaction record of a transaction may be used to represent a start time of the entire transaction. The capture and apply processes may work cooperatively to establish a safe time point in the form of a particular system change number in logs to begin mining, under various circumstances such as in an initial startup state, in a steady state, in a process restart scenario in the middle of checkpoint free log mining, or in a transition between the checkpoint mode and the checkpoint free mode.

Abstract: Configuring an n-way multi-master information sharing topology. Adding a new node (e.g., database server) to the information sharing topology can be implemented as follows. Initially, the new node is added as a slave of a particular co-master in the information sharing topology. The objects to replicate are instantiated on the new node by propagating data from the particular co-master to the new node. Furthermore, a capture process is created on the particular co-master to send changes to the objects to the slave. Meanwhile, the co-masters continue to propagate changes to each other. To promote the slave to a master, changes to objects stored at the slave are propagated to each of the co-masters. Furthermore, changes at each of the masters are propagated to the promoted node.

Abstract: In accordance with an embodiment of the present invention, an information sharing mechanism comprising a memory structure may be provided in a database system. In an embodiment, mined information transferred by a capture process to an associated apply process can be written into the memory structure without taking any latch. Similarly, the mined information can be read by the apply process from the memory structure without taking any latch. The capture and apply processes may work cooperatively to establish a safe point in log mining under various circumstances such as in an initial startup state, in a steady state, in a process restart scenario in the middle of information sharing. In some embodiments, the information sharing mechanism supports both checkpoint-free and checkpoint modes of log mining by the capture process. In addition, both the capture process and the apply process may employ an eager apply approach to increase processing capacity.

Abstract: Methods and apparatus for adaptive encoding of data such as for example video data. In one exemplary embodiment, a real-time video encoder is disclosed that changes video encoding processes to produce the best quality encoded video whilst maintaining a target encoding frame rate, according to one or more operating constraints.

Abstract: Performing an operation directly on data stored in a database table provides for avoiding generation and processing of SQL statements. A Data Layer interface, comprising a set of APIs, allows internal database server components to call directly to the Data Layer for making fast row changes to a table. According to an embodiment, before making any row change to a table through this Data Layer interface, a shared state data structure is created to hold the metadata about the table. A single shared state can be used for all DML changes to a particular table regardless of what columns are updated or inserted during each DML operation. When a process needs to change a row, the process uses a mutable state based on the shared state of the table.

Abstract: Systems, methodologies, media, and other embodiments associated with managing of a distributed database are described. One exemplary system embodiment includes an input logic configured to obtain information associated with a distributed database where the distributed database comprises a plurality of databases. An analysis logic analyzes the information obtained from the distributed database to determine performance information associated with the distributed database and, an output logic can provide information regarding the performance information associated with the distributed database.

Abstract: Inter-processor communication systems and methods that define within the instruction set of the microprocessor a command for directing the microprocessor to relinquish control over at least one of the microprocessor's internal registers. The microprocessor may then signal a communication interface that collects data from external sources. The communication interface takes control over the internal register released by the microprocessor and inputs the collected external data directly into the internal register of the microprocessor. Once data is place into the internal register, control of that register may be returned to the microprocessor.

Abstract: A method and apparatus for replicating data between heterogeneous databases is provided. Data is replicated between two heterogeneous databases with the use of a volatile storage queue, enabling the rapid replication of data across databases provided by different vendors or operating on different platforms. According to one embodiment, an in-memory queue is used to queue change operations to be performed on a target data repository. The change operations may be operations that were applied to a source data repository. An apply process retrieves the change operations from in-memory queue and commits the change operations to persistent storage. When the change operations have been committed, the apply process notifies the source platform that the particular change operation has been stored.

Abstract: Efficiently replicating XML data among databases includes techniques for (a) replicating XML data involved with an insert operation; (b) replicating XML data involved with an update operation; (c) leveraging existing relational replication techniques for XML data stored in shredded form using object-relational constructs; and (d) replicating XQuery Data Model sequences. Each technique reduces the amount of information that would otherwise need to be transmitted over a network for XML data replication purposes.

Abstract: Methods and apparatus adapted for enhancing the throughput of a digital processor (e.g., microprocessor, CISC device, or RISC device) through use of a direct memory access (DMA) mechanism. In one embodiment, the processor comprises a “soft” RISC-based processor core that is both user-extensible and user-configurable. The core comprises a functional process or unit (DMA assist) that is coupled to the processor's extension logic and which facilitates throughput by, among other things, ensuring that the CPU and processor extension logic can operate on data in parallel in an efficient manner. In one variant, a parallel datapath (including a buffer) is used in conjunction with the aforementioned DMA assist so as to permit the processor extension logic to efficiently operate in parallel with the CPU.

Abstract: A method, system, and computer program product for transmitting a redo stream from a database to one or more distributed database systems, upon which applications that process the redo stream are implemented, and which maintains the data dictionaries by replicating the multiple versions of the schema objects to data dictionaries in the distributed database systems. A method of maintaining a multi-version data dictionary includes generating a logical redo stream, inserting procedure calls to be used to populate the multi-version data dictionary into the generated logical redo stream, transmitting the logical redo stream to the multi-version data dictionary, and executing the procedure calls at the multi-version data dictionary to populate the multi-version data dictionary.