Abstract: A method, computer program, and database system are disclosed for processing a database query that includes one or more expressions. The method includes resolving columns in one or more of the expressions. Expression optimization is performed on one or more of the expressions. Afterward, further query optimization is performed.

Abstract: A system, method, and computer-readable medium that facilitate in-database supervised discretisation mechanisms which improve data classification are provided. The disclosed mechanisms provide an efficient, automatic, and repeatable way to perform data discretisation without human intervention. Efficient processing of large and complex unknown data is provided that advantageously does not require the data being analyzed to be processed outside the database. The disclosed mechanisms may use an External Stored Procedure to avoid multiple joins of large tables and minimize the number of full table scans and, consequently, provide better performance than contemporary mechanisms. The disclosed system produces intermediate results in tables which may be conveyed to a visualization subsystem thereby providing users a better understanding of the data distribution in each category.

Abstract: A method and system for eliminating unnecessary statistics collections for query optimization in a database stored on a computer. Statistics are unnecessary when a re-generated query execution plan that does not use the statistics is equivalent to an original query execution plan that uses the statistics. To determine this, an original query execution plan is created for each query in a specified workload using the statistics in the database. A search is performed of the statistics in order to enumerate one or more candidate sets of statistics to be eliminated. One or more of the candidate sets of statistics are removed from consideration prior to creating the re-generated query execution plan for each query in the specified workload.

Abstract: A computer-implemented method, apparatus and article of manufacture for optimizing execution of database queries in a computer system. In one embodiment, the steps and functions include: generating first and second query execution plans for first and second requests, wherein the first and second query execution plans are each comprised of one or more steps that scan a specified table in a database stored on the computer system in order to retrieve data from the table; and executing the first and second query execution plans, wherein intelligent query dispatching is performed on the steps of the first and second query execution plans to ensure that the steps share the data retrieved from the table and cached in memory.

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 computer implemented method of and system for capturing, storing and organizing quality feedback information associated with products sold by a retail enterprise. The quality feedback information is stored and organized within a relational database in accordance with a logical data model comprising a plurality of entities and relationships defining the manner in which quality feedback information is stored and organized within the relational database. The relational database, populated with quality feedback information, provides the retail enterprise with the means to analyze and improve retail operations, to better manage store inventory, and more efficiently manage product sales and returns.

Abstract: Embodiments of the present invention provide a hardware accelerator that assists a host database system in processing its queries. The hardware accelerator comprises special purpose processing elements that are capable of receiving database query/operation tasks in the form of machine code database instructions, execute them in hardware without software, and return the query/operation result back to the host system.

Abstract: A system, method, and computer-readable medium for optimizing the performance of outer joins in a parallel processing system are provided. Predicates involving only attributes of a left table of a left outer join are pushed down to the outer relation for left outer joins having join predicates involving left table attributes and/or predicates involving attributes of both the right and left table. In such an instance, the rows of the left table may be partitioned into two sub-relations according to the predicate involving only attributes of the left table. Rows of the left table are allocated to a first sub-relation if the rows satisfy the predicate involving only attributes of the left table and rows of the left table are allocated to a second sub-relation if the rows fail to satisfy the predicate involving only attributes of the left table. Accordingly, only rows of the first sub-relation are required to be left outer joined with the right table.

Abstract: A method of systematically applying parameter evaluation techniques to large numbers of complex segmented models used for managing and analyzing a segmented manufacturing or supply chain process. These models include a plurality of segment models, each segment model representing a process segment within the segmented manufacturing or supply chain process and comprising a mathematical expression including at least one parameter. The method compares predicted values generated by a segment model with actual observed values to determining a score representative of the performance of the segment model. New parameters for the mathematical equation associated with the segment model are determined through statistical techniques when the model score indicates an unacceptable performance of the segment model. The segment models may be evaluated and updated in parallel and without manual intervention.

Abstract: A database system receives a transaction that selects values of a column of a first table based on one or more conditions, the column in the first table being according to a first data type. The database system transforms the first data type to a second, different data type. The selected values of the column according to the second data type are stored in the second table.

Abstract: Embodiments of the present invention provide a hardware accelerator that assists a host database system in processing its queries. The hardware accelerator comprises special purpose processing elements that are capable of receiving database query/operation tasks in the form of machine code database instructions, execute them in hardware without software, and return the query/operation result back to the host system.

Abstract: Techniques for integrating disparate data access mechanisms are provided. A user attempts data access against an infocube and its data access mechanism. Transparently, that access attempt is translated into a format recognized and processed by a relational database access mechanism to produce results. The results are then translated from a relational database format back to an infocube format and presented to the user within the infocube's data access mechanism.

Abstract: Optimizing the execution of a query in a multi-database system includes identifying a region within a table, the table being referenced in the query. The region is stored on a data-storage device on a first of the system databases in the multi-database system. The region is stored on a data-storage device on a second of the system databases in the multi-database system, the second system database being a different system database than the first system database. A first access plan for the query is developed, the first access plan comprising accessing the version of the region stored on the first system database. A second access plan for the query is developed, the second access plan comprising accessing the version of the region stored on the second system database. A selection is made between the first access plan and the second access plan to execute the query. The query is executed using the selected access plan to produce a result. The result is stored.

Abstract: A method of estimating the average response time and average I/O size that can be used as an alternative for or addition to existing response time and I/O estimation techniques. One method involves initializing values for an average response time and an average I/O size, and initializing an angle. Measurements of the I/O size and response times are received. The technique involves adjusting the average I/O size using the current value of the average I/O size and the received I/O size measurement. The average response time is adjusted using the current value for the average response time and the received response time measurement. The angle value is adjusted using the adjusted average I/O size, the current angle value and the I/O size and time measurements. The slope and y-intercept of a line, formed by plotting the average I/O size verses response time, can then be reported.

Abstract: In a database system, compression user-defined data types (UDTs) are defined to enable compression of data. Each compression UDT is associated with one or more UDT methods to compress data according to one or more respective compression algorithms. Also, one or more data structures are associated with data stored according to each compression UDT to store values pertaining to the compression of the data.

Abstract: A system, method, and computer-readable medium for optimizing join operations in a parallel processing system are provided. A respective set of rows of a first table and a second table involved in a join operation are distributed to each of a plurality of processing modules. The join operation comprises a join on a first column of the first table and a second column of the second table. Each of the plurality of processing modules redistributes at least a portion of the rows of the first table distributed thereto substantially equally among the other processing modules and duplicates at least a portion of the rows of the second table distributed thereto among the plurality of processing modules. The disclosed optimization mechanisms provide for reduced spool space requirements for execution of the parallel join operation.

Abstract: A system, method, and computer-readable medium that facilitate workload management in a computer system are provided. A workload's system resource consumption is adjusted against a target consumption level thereby facilitating maintenance of the consumption to the target consumption within an averaging interval by dynamically controlling workload concurrency levels. System resource consumption is compensated during periods of over or under-consumption by adjusting workload consumption to a larger averaging interval. Further, mechanisms for limiting, or banding, dynamic concurrency adjustments to disallow workload starvation or unconstrained usage at any time are provided.

Abstract: Techniques are presented for skew exception detection within a parallel processing environment. A potential exception is detected when a highest load of a processor within the parallel processing environment exceeds an average load within the parallel processing environment by a given threshold. The potential exception can become a legitimate exception when it exists for a qualified period or time or when it exists and no qualified period of time is noted. In an embodiment, checks for the potential exception occur and are wholly contained within a given configurable interval.

Abstract: A system, such as a database system, includes a shared library having plural routines. A linking procedure is used in which a routine (referred to as a “first routine”) is linked to a stub library containing stub programs corresponding to other routines that the first routine is authorized to invoke. If no linking error occurs, the first routine is then linked to the shared library. In some implementations, the first routine is one of a user-defined method (UDM), user-defined function (UDF), or stored procedure created in response to a database query language (e.g., Structured Query Language or SQL) statement.

Abstract: Apparatus, systems, and methods may operate to receive a set of ordered user-selected compression rules as a compression rule set comprising at least one compression threshold condition, to create or transform a database object with rows to be selectively compressed according to the compression rules in the compression rule set (providing a transformed object), and to publish at least a portion of the transformed object to one of a storage medium or a display screen. Other apparatus, systems, and methods are disclosed.