Abstract: Data can be stored based on one or more indications and one or more other storage criteria. The indications can effectively indicate or identify a storage level for storing data in a multi-storage system. The indications, however, need not be the only basis for storing the data object in a multi-storage system as one or more other storage criteria can also be considered. As a result, the indication can be used to effectively influence data storage but other storage criteria can be used as well to prevent adverse effects caused by undue influence and to ensure the overall efficiency of the system. Also, the one or more other storage criteria can be evaluated or reevaluated on a continual basis.

Abstract: Data or one or more operations can be provided, based on one or more characteristics associated with the data and/or operations, to a designated computing group or pool of computing resources designated for handling the data and/or operations with the particular data characteristic(s). The designated computing group can, for example, be one of multiple computing groups in the same system or device. As such, all of the computing groups can still function together in the same system or device, for example, in parallel. However, each one of the multiple computing groups can, for example, be defined or predefined to include one or more computing resources that are more suitable for storing and/or processing data with one or more data characteristics or handle operations with one or more determined characteristics.

Abstract: Based on one or more predicated results (e.g., estimations of the actual results) associated with one or more iterations and/or sub-queries of an iterative or recursive database query, it can be determined whether to use an execution plan (e.g., a current execution plan used to execute one or more iterations) to execute one or more other iterations and/or sub-queries of the iterative or recursive database query. Consequently, use of the execution plan to execute the one or more other iterations and/or sub-queries of the iterative or recursive database query can be disallowed. As a result, the iterative or recursive database query can be executed more efficiently. The determination of whether to use an execution plan can, for example, be performed by determining whether an actual result obtained by executing one or more iterations differs or diverges more than a determined value from an estimated result of the same iteration(s).

Abstract: The number of iterations or self joins required to execute a recursive database query can be estimated. It will be appreciated that this estimation can be used to plan the execution of the recursive query and can be made in various ways and for various applications. By way of example, an estimated number of iterations or self joins required to execute a recursive database query (e.g., 12) can be used as a basis to determine or plan an optimal execution plan. For example, given an estimated twelve (12) iterations, an execution plan can be determined for executing at least the first three (3) iterations or for executing every there (3) iterations, whereas for an estimated twenty (21) iterations required to complete a recursive database query, an execution plan can be determined for the first five (5) or six (6) iterations, and so on.

Abstract: A system, method, and computer-readable medium that facilitate efficient use of cache memory in a massively parallel processing system are provided. A residency time of a data block to be stored in cache memory or a disk drive is estimated. A metric is calculated for the data block as a function of the residency time. The metric may further be calculated as a function of the data block size. One or more data blocks stored in cache memory are evaluated by comparing a respective metric of the one or more data blocks with the metric of the data block to be stored. A determination is then made to either store the data block on the disk drive or flush the one or more data blocks from the cache memory and store the data block in the cache memory. In this manner, the cache memory may be more efficiently utilized by storing smaller data blocks with lesser residency times by flushing larger data blocks with significant residency times from the cache memory.

Abstract: A method and system for adjusting product store order quantities when a retail store is moving a replenishment source from a current distribution center to a new distribution center. The method determines a last delivery date for a last product order from the current distribution center to be placed prior to a product replenishment source change date, and a first delivery date for a first product order from the new distribution center to be placed following the product replenishment source change date; and compares the two delivery dates to determine which delivery will occur first. When the first delivery date for new distribution center predates the last delivery date for the current distribution center, the last product order from the current distribution center is suspended.

Abstract: An improved method and system for forecasting product demand using a causal methodology, based on multiple regression techniques. The improved causal method identifies year-over-year trending effects within historical product demand data, removes the trending effects from the calculation of seasonal factors used in determining product demand forecasts, calculates trend factors from the identified trending effects, and applies the trend factors and de-trended seasonal factors to initial product demand forecasts when determining final demand forecasts for the products.

Abstract: Several methods and a system of a replicated service for write ahead logs are disclosed. In one embodiment, a method includes persisting a state of a distributed system through a write ahead log (WAL) interface. The method also includes maintaining a set of replicas of a WAL through a consensus protocol. In addition, the method includes providing a set of mechanisms for at least one of detection and a recovery from a hardware failure. The method further includes recovering a persistent state of a set of applications. In addition, the method includes maintaining the persistent state across a set of nodes through the hardware failover. In one embodiment, the system may include a WAL interface to persist a state of a distributed system. The system may also include a WAL replication servlet to maintain and/or recover a set of replicas of a WAL.

Abstract: A system includes a multi-system database management system having a plurality of database systems. An index selection subsystem combines sets of query information from respective ones of the plurality of database systems into a workload. The index selection subsystem then generates candidate indexes from the workload, and selects recommended indexes from the candidate indexes based on one or more criteria.

Abstract: Excess capacity of a database system can be used for learning activities in a controlled computing environment. In this context, excess capacity of a database system can be used as needed and/or on a temporary basis. Furthermore, learning activities can be performed without requiring the use of the capacity that is configured or has been allotted for various other database operations, including those deemed, especially by the users of database system, to serve a main function or a more important purpose. As a result, learning can be performed without adversely affecting other operations deemed to be more critical, especially by the users of databases. Learning activities associated with a database environment can, for example, include learning operations directed to optimization of database queries, for example, by using a basic feedback or an expanded or active learning.

Abstract: A system, method, and computer-readable medium that facilitate management of data skew during a parallel join operation are provided. Portions of tables involved in the join operation are distributed among a plurality of processing modules, and each of the processing modules is provided with a list of skewed values of a join column of a larger table involved in the join operation. Each of the processing modules scans the rows of the tables distributed to the processing modules and compares values of the join columns of both tables with the list of skewed values. Rows of the larger table having non-skewed values in the join column are redistributed, and rows of the larger table having skewed values in the join column are maintained locally at the processing modules. Rows of the smaller table that have non-skewed values in the join column are redistributed, and rows of the smaller table that have skewed values in the join column are duplicated among the processing modules.

Abstract: A multistage interconnect network (MIN) capable of supporting massive parallel processing, including point-to-point and multicast communications between processor modules (PMs) which are connected to the input and output ports of the network. The network is built using interconnected switch nodes arranged in 2 log.sub.b N stages, wherein b is the number of switch node input/output ports, N is the number of network input/output ports and log.sub.b N indicates a ceiling function providing the smallest integer not less than log.sub.b N. The additional stages provide additional paths between network input ports and network output ports, thereby enhancing fault tolerance and lessening contention.

Abstract: A multiprocessor system intercouples the processors with an active logic network having a plurality of priority determining nodes. Messages applied concurrently to the network in groups are sorted, using the data content of the messages, to a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priority scheme and are transferred in contending groups with prioritization on the network. Using data, status, control and response messages, and different multiprocessor modes, the system is particularly suited for configuration in a relational data base machine having capability for maintaining an extended data base and handling complex queries.

Abstract: A multiprocessor system intercouples the processors with an active logic network having a plurality of priority determining nodes. Messages applied concurrently to the network in groups are sorted, using the data content of the meassages, to a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priorty scheme and are transferred in contending groups with prioritization on the network. Using data, status, control and response messages, and different multiprocessor modes, the system is particularly suited for configuration in a relational data base machine having capability for maintaining an extended data base and handling complex queries.

Abstract: A multiprocessor system intercouples the processors wtih an active logic network having a plurality of priority determining nodes. Messages applied concurrently to the network in groups are sorted, using the data content of the messages, to a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priority scheme and are transferred in contending groups with prioritization on the network. Using data, status, control and response messages, and different multiprocessor modes, the system is particularly suited for configuration in a relational data base machine having capability for maintaining an extended data base and handling complex queries.

Abstract: A system for dynamically partitioning processors in a multiprocessor system intercoupled by a network utilizes, in association with each processor, a network accessible, locally changeable memory section. An available one of a number of common dynamic group addresses in each of the memories is reserved for a subgroup for the performance of subtasks within an overall task, and members of the group are designated as they receive messages to be processed. The members then locally update status words which establish membership, group validity and semaphore conditions, so that transactions may be initiated, coordinated and terminated with minimum involvement of processors that have no relevant subtasks. When the full task is completed the dynamic group is relinquished for use when a new task is to be undertaken. The system enables many tasks to be carried out concurrently with higher intercommunication efficiency.

Abstract: A multiprocessor system intercouples the processors with an active logic network having a plurality of priority determining nodes. Messages applied concurrently to the network in groups are sorted, using the data content of the messages, to a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priority scheme and are transferred in contending groups with prioritization on the network. Using data, status, control and response messages, and different multiprocessor modes, the system is particularly suited for configuration in a relational data base machine having capability for maintaining an extended data base and handling complex queries.

Abstract: A multiprocessor system intercouples the processors with an active logic network having a plurality of priority determining nodes. Messages applied concurrently to the network in groups are sorted, using the data content of the messages, to a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priority scheme and are transferred in contending groups with prioritization on the network. Using data, status, control and response messages, and different multiprocessor modes, the system is particularly suited for configuration in a relational data base machine having capability for maintaining an extended data base and handling complex queries.

Abstract: A multiprocessor system intercouples processors with an active logic network having a plurality of priority determining nodes. Messages are applied concurrently to the network in groups from the processors and are sorted, using the data content of the messages to determine priority, to select a single or common priority message which is distributed to all the processors with a predetermined total network delay time. Losing messages are again retried concurrently in groups at a later time. Message routing is determined by local acceptance or rejection of messages at the processors, based upon destination data in the messages. All messages occupy places in a coherent priority scheme and are transferred in contending groups with prioritization on the network.