Automatic recognition and rerouting of queries for optimal performance
US6460027B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 14, 1998 |
| Grant date | Oct 1, 2002 |
| Priority date | — |
| Expiry date | Sep 14, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99934
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A method, apparatus, and article of manufacture for optimizing database queries uses a derived summary table, wherein a definition of the summary table is based on a full select statement that is materialized in the table and describes how the summary table was derived. The summary table definition can be a complex query involving nested GROUP BY operations as well as complex HAVING clauses with subqueries or join operations. A query is analyzed using subsumption tests between the query and the definition of the summary table to determine whether expressions occurring anywhere in the query, but not in the summary table, can be subsumed in the summary table. In performing the query, an expression in the query is subsumed in the summary table when the expression can be re-derived from one or more of the columns of the summary table.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.