Compile-time optimizations of queries with SQL spreadsheet
US7177855B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 6, 2003 |
| Grant date | Feb 13, 2007 |
| Priority date | — |
| Expiry date | Aug 3, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99935
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Described herein are optimizations and execution strategies for spreadsheet extensions to SQL. The partitioning of data, as specified in a spreadsheet clause, provides a way to parallelize the computation of spreadsheet and to provide and improve scalability. Even if the partitioning is not explicitly specified in the spreadsheet clause, the database optimizer can automatically infer the partitioning in some cases. Efficient hash based access structures on relations can be used for symbolic array addressing, enabling fast computation of formulas. When rewriting SQL statements, formulas whose results are not referenced in outer blocks can be removed from the spreadsheet clause, thus removing unnecessary computations. The predicates from other query blocks can be moved inside query blocks with spreadsheets clauses, thus considerably reducing the amount of data to be processed. Conditions for validity of this transformation are given.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.