Patent Number: 6,298,342

Title: Electronic database operations for perspective transformations onrelational tables using pivot and unpivot columns

Abstract: A "pivot" operation rotates the data items in a relational database tableso that certain data values in the table become column names of thepivoted table, and the data items of a specified value column appear incorresponding rows in the new columns of the pivoted table. A pivot listspecifies that only certain values of the pivot column data itemsparticipate in the operation. Additional columns of the input table appearas columns in the output table; the rows of the output table are groupedby equal data-item values in these grouping columns. An "unpivot"operation provides the inverse of the pivot operation. Both operations maybe nested in an SQL user query at the algebraic level. The operationsoccur in the search engine of a relational database management system, andmay also be invoked as part of an optimization of another query.

Inventors: Graefe; Goetz (Bellevue, WA), Alger; Jeff (Redmond, WA)


International Classification:

Expiration Date: 10/02/2013