Abstract: A method and system for allocating storage space from storage devices within a computer system. The storage devices are grouped into respective homogeneous sets in which identical storage devices are included in the same homogeneous set. In accordance with the method and system, following receipt of an allocation request for storage space one or more stored response values are checked, the response values associated with at least one homogeneous set. The stored value or values represent the average response time of storage devices within the set. The homogenous set with the lowest average response time is selected. One or more stored allocation values are then checked that are associated with at least one storage device within the selected homogeneous set. The stored allocation value or values represent the current allocations of the associated storage device.

Abstract: A method of archiving a set of source tables in a database system. Each source table has a plurality of rows. Initially, a consistency point for the set of source tables is established. The database system creates a log record for each change (insert, modify, or delete) effected to a row of the source tables subsequent to the consistency point. Substantially all source table rows are copied to an archive (a data storage object that is external to the database system). Then the accumulated log records for the affected source tables are distilled and appended to the archive.

Abstract: Execution of a query is optimized. A plurality of plans for executing the query on a multi-database system are analyzed. A first plan having a first step and a second step is selected. The first step of the first plan is executed. The plan selection is re-evaluated before executing the second step of the first plan. A second plan of the plurality of plans for executing the query is executed to produce a result. The result is stored.

Abstract: A computer-implemented method, apparatus and article of manufacture for optimizing a database query. Resource usage of one or more resources of the computer system are monitored. A condition code representative of the monitored resource usage is stored. A cost model is modified using the stored condition code. A query execution plan is generated for the database query using the modified cost model. The query execution plan is then executed in order to retrieve data from a database stored on the computer system, wherein the retrieved data is presented to a user for subsequent use and analysis.

Abstract: A query is received. It is determined that the query includes an inner join between a parent table and a child table. It is determined that the following relationships exist between the parent table and the child table: referential integrity (“RI”) between a primary key attribute (pk) in the parent table and a foreign key attribute (fk) in the child table, where “attribute” is defined to mean one or more columns, and a temporal relationship constraint (“TRC”) between a period attribute in the parent table and a TRC-attribute in the child table, the TRC-attribute being a date or time attribute. It is determined that the query does not access any attribute in the parent table other than the pk. It is determined that the query specifies an equality predicate of the form pk=fk. It is determined that the query selects a snapshot from the parent using a predicate of the form parent.[period attribute] contains a point in time (t1).

Abstract: A computer receives a query for optimization. The query includes a SEQUENCED join between a temporal parent table and a temporal child table. The parent table has one or more rows. The child table has one or more rows. The parent table has a Primary Key (“PK”) column having a value for each row. The parent table has a temporal dimension having a value for each row. The child table has a Foreign Key (“FK”) column having a value for each row. The child table has a temporal dimension. The child table's temporal dimension has a value for each row. The computer determines that the query, the parent table, the child table, and the join satisfy a set of CURRENT temporal join elimination criteria. The computer determines that the query, the parent table, the child table, and the join satisfy a set of SEQUENCED temporal join elimination criteria. In response, the computer eliminates the join from the query to produce an optimized form of the query.

Abstract: A method of searching a multilevel partitioned database includes receiving a query data from the multilevel partitioned database. At least for one level partitions are dynamically included. For some levels, partitions may also be statically included for execution of the query. The query is the executed over the partitions that are both dynamically and statically included. In one example, the cost of joining two tables in a multilevel partitioned database includes determining level partitions that can be statically included, estimating level partitions that will be dynamically considered for the join, and determining a cost as a function of the estimated statically included level partitions and estimated dynamically included level partitions.

Abstract: A virtual regulator monitors and manages a plurality of database systems in a domain. Each of the database systems is tuned for a particular type of workload, and the virtual regulator or multiple virtual regulators running in parallel routes a set of one or more queries to a particular database system within the domain based on a cost function for each database system.

Abstract: A system, method, and computer-readable medium for automatic and dynamic control of optimizer settings in a large complex system environment are provided. The described mechanisms significantly increase the potential of achieving Service Level Goals for classes of queries where optimizer aggression is needed. Confidence threshold parameters are automatically controlled to facilitate generation of query execution plans to conform with associated Service Level Goals.

Abstract: Techniques for database rule ordering and processing are provided. Structured Query Language (SQL) statements are iterated to identify processing dependencies and a processing order is generated. The SQL statements are automatically modified to enforce the processing order and the modified SQL statements are executed against a database.

Abstract: Techniques for selective compression of database information are presented. Selective first portions of a field associated with a database table are identified along with metadata associated with the database table. The first portions and the metadata are then compressed by selecting one or more compression algorithms in response to compression capabilities associated with the algorithms.

Abstract: The frequency with which data is accessed within the system may be periodically monitored and a corresponding access frequency quantifier assigned to the data is updated accordingly. The data access frequency quantifier may be associated with a storage device zone speed quality rating. The association between data access frequency quantifiers and the storage device zone speed quality ratings may be made in a hierarchical association such that quantifiable differentials may be ascertained between a particular access frequency quantifier and a storage device zone speed quality rating. In this manner, when no storage zone having a speed quality rating that is associated with data having a particular access frequency quantifier is available for storage of the data, a storage zone having a speed quality rating more proximate the speed quality rating associated with the access frequency quantifier may be identified for migration.

Abstract: An improved method for forecasting and modeling product demand for a product during promotional periods. The forecasting methodology employs information about prior promotional demand forecasts, prior product sales, and the data dispersion and the number of data samples in a product class hierarchy to dynamically determine the optimal level at which to compute promotional uplift coefficients. The methodology calculates confidence values for promotional uplift coefficients for products at each level in a merchandise product hierarchy, and uses the confidence values as a filter to determine the optimal level for promotional uplift aggregation.

Abstract: A system for managing a plurality of systems, includes a domain comprised of a plurality of systems, wherein the systems are managed by one or more closed-loop system management (CLSM) regulators. A virtual regulator manages operational characteristics of the domain and the plurality of systems, by communicating with the CLSM regulators to monitor the systems' states, events and conditions within the domain and to adjust the systems' operational characteristics in response to the systems' states, events and conditions.

Abstract: A system and method for using failure casting to manage failures in a computer system. In accordance with an embodiment, the system uses a failure casting hierarchy to cast failures of one type into failures of another type. In doing this, the system allows incidents, problems, or failures to be cast into a (typically smaller) set of failures, which the system knows how to handle. In accordance with a particular embodiment, failures can be cast into a category that is considered reboot-curable. If a failure is reboot-curable then rebooting the system will likely cure the problem. Examples include hardware failures, and reboot-specific methods that can be applied to disk failures and to failures within clusters of databases. The system can even be used to handle failures that were hitherto unforeseen—failures can be cast into known failures based on the failure symptoms, rather than any underlying cause.

Abstract: A database system includes database software to receive a query specifying a join of plural base tables, and to determine whether a foreign key and primary key relationship exists between join columns specified by the query and a materialized view definition. Based on the existence of the foreign key and the primary key relationship between join columns specified by the query and the materialized view definition, the database software determines that a result for the received query is to be computed from the materialized view.

Abstract: Techniques for constructing and using run-time JAVA Archive (JAR) files for JAVA Stored Procedures (JSPs) are provided. JSP methods referenced by an application via a plurality of different JAR files are extracted and packed into a single packed JAR file. When the application tries to execute a JSP, the attempt to process the JSP methods is redirected to a new JSP that calls the single packed JAR file.

Abstract: A method, system, and computer program for optimizing execution of a DML statement on a temporal database are disclosed. A first execution package is provided to an execution engine. The first execution package includes a plurality of operations to be executed if the contents of a row in a table in the temporal database indicate the row has a first temporal condition. A second execution package is provided to the execution engine. The second execution package includes a plurality of operations to be executed if the contents of the row in the table in the temporal database indicate the row has a second temporal condition. The execution engine is run to produce a result. The result is saved.

Abstract: Techniques for collecting statistics of column data or R-Tree indexes are provided. A distributed database system includes a plurality of processing nodes controlling portions of spatial data. The nodes are instructed to create minimum bounding rectangles (MBR's) for their spatial data or R-Trees. The individual MBR's are merged and reformatted into a grid of equally sized cells. Each processing node is provided a copy of the grid to update based on statistics of each processing node's spatial data for a target table. The updated grids are then merged into a single grid and used by an optimizer to evaluate queries before the queries are executed.

Abstract: A database system constructs representation for predicate expressions invoking user-defined routines. A first representation is constructed if an indicator has a first value, and a second representation is constructed if the indicator has a second value. Based on which representation is used, an optimizer in the database system selects use of indexing and/or statistics and/or other performance-enhancement features in generating a query plan.