Abstract: Provided is a method, system, program, and data structures for making data available to an application program. A result table is generated including rows corresponding to a subset of rows in a base table having data in one or more columns that satisfy a query predicate clause. The result table includes, for each row, a location identifier of the corresponding row in the base table and a column for each column in a query select list. The result table is accessed to return requested data from the base table to the application program.

Abstract: Disclosed is a system, method, and program for performing a join operation on a multi-column table and at least two satellite tables having a join condition. Each satellite table is comprised of multiple rows and at least one join column. Each multi-column table is comprised of multiple rows and at least one column corresponding to the join column in each satellite table. A join operation is performed on the rows of the satellite tables to generate a first join result comprising concatenations of the rows of the satellite tables. Less than all the concatenated rows in the first join result that satisfy the join condition are then selected. The selected concatenated rows in the first join result are then joined to the multi-column table.

Abstract: A method, apparatus, and article of manufacture for a computer implemented groupby aggregation system. Groupby aggregation is performed when a statement is executed in a database stored on a data storage device, which is connected to a computer. Initially, data elements are input into a tournament tree from an input sequence. Then, a winner of a tournament in the tournament tree is identified. The winner is recycled into the tournament tree.

Abstract: A method, apparatus, and article of manufacture for an index screening system. A query is executed to access data stored on a data storage device connected to a computer. In particular, while accessing one or more indexes to retrieve row identifiers, index matching predicates in the query are applied to select row identifiers and index screening predicates in the query are applied to eliminate one or more selected row identifiers.

Abstract: A method and apparatus for generating static, dynamic and hybrid sparse indices for use with workfiles used by SQL queries in a relational database management system.

Abstract: A method, apparatus and article for manufacture for generating static, dynamic and hybrid sparse indices for use with workfiles used by SQL queries in a relational database management system. A workfile and a sparse index structure are temporarily created in the computer during execution of the query by the computer. The workfile stores intermediate relations resulting from execution of a portion of the SQL query, wherein the intermediate relations comprise sorted rows for an inner table referenced in the SQL query. The sparse index structure contains one or more entries indicating at least an approximate location for at least some of the rows in the workfile. As one or more rows from an outer table referenced in the SQL query are retrieved, the entries of the sparse index structure are searched for a closest matching entry for each retrieved row. The sorted workfile is then scanned for a row matching each retrieved row using the closest matching entry from the sparse index structure as a starting position.