Method and apparatus for optimizing queries across heterogeneous databases
US5943666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 15, 1997 |
| Grant date | Aug 24, 1999 |
| Priority date | — |
| Expiry date | Sep 15, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S707/99934
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A heterogeneous database system includes plural databases, one database acting as a system manager which performs functions to provide a transparent user interface that encompasses both the system manager database and other databases. The system manager includes a memory which stores (i) a database management procedure, (ii) a catalog of database functions that are supported by the plural databases, and (iii) a query optimizer procedure. A processor is responsive to a user query which requires data stored at a remote database, to execute the query optimizer procedure. The query optimizer procedure employs entries from the catalogue relating to database functions supported by both the system manager database and the remote database and establishes query plans for responding to the query. A first query plan is based upon execution at the remote database and a second query plan is based upon execution at the system manager database. The query optimizer then chooses one of the query plans in accordance with a determined criteria and causes the selected plan to be executed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.