Abstract: A method of mapping data into a table includes identifying pointers of a source portion and target portion and switching the metadata pointers of the target portion to be those of the source portion. Upon switching the metadata pointers, the data of the source portion is mapped into the target portion of the table. The method of mapping exhibits the advantage of performing the mapping operation by moving metadata and not table content data. The method may be used on any portion of a database including files, tables, partitions, and indexes. In one embodiment, the switching of pointers includes copying the target portion metadata into temporary storage, copying source portion metadata into the target portion metadata, and copying metadata from the temporary storage into the source portion metadata.

Abstract: A system, method and computer-readable medium containing computer-executable instructions for tuning queries is provided. A query processor converts a query into an execution plan in a hierarchical format that conforms to a standardized schema. In one embodiment of the invention, the hierarchical format employed is XML.

Abstract: A method and apparatus for distributing data of a table across a parallel data base system having a plurality of interlinked database nodes. The table is partitioned in accordance with a predetermined partitioning arrangement and data of the table is distributed across a subset of the nodes in accordance with the partitioning arrangement. The partitioning arrangement can comprise horizontal or vertical partitioning. The partitioning arrangement can comprise a partitioning map defining the relationship of partitions of the table to said subset of nodes.

Abstract: A method for localizing execution of subqueries and determining collocation of execution of subqueries in a shared-nothing database. The concept of compatible partitioning is used to localize database operations in order to eliminate excess processes and communication, and thereby improve response time and throughput for the database management system. The method reduces the number of process by reducing the number of nodes involved in processing a query and by combining multiple processes.

Abstract: A method for localizing execution of subqueries and determining collocation of execution of subqueries in a shared-nothing database. The concept of compatible partitioning is used to localize database operations in order to eliminate excess processes and communication, and thereby improve response time and throughput for the database management system. The method reduces the number of process by reducing the number of nodes involved in processing a query and by combining multiple processes.