Resources Contact Us Home
Query optimization system and method

Image Number 11 for United States Patent #6546381.

A query optimization system and method are particularly suitable for generating a least cost query plan expressible on a plurality of heterogeneous database schemas that are restructuring views of each other. The query optimization system receives a query against one of the tables and converts it to a plurality of alternate queries, each formatted for the particular schema of a different one of the plurality of heterogeneous tables. In generating the alternate queries, the system may utilize SchemaSQL view definitions and may employ restructuring operators expressing and capable of conducting a restructuring of a table into a restructuring view of the table. A middleware system involving a canonical schema and a virtual canonical table may also be employed to express a mapping between restructuring views for purposes of query conversion. The alternate queries may be costed and optimized and a query plan returned that has a least cost or service time involved.

  Recently Added Patents
Electronic device and recording medium
Methods and compositions for inhibition of neutrophil exocytosis
System and method for solving connection violations
Method and system for billing based on color component histograms
Configurable logic cells
Functionalized main chain polymers
Probe for ultrasound diagnostic apparatus
  Randomly Featured Patents
Combustion system with precombustor
Fill limit vapor valve with variable vapor venting capability
Process for the preparation of a RAF kinase inhibitor and intermediates for use in the process
Generator for supplying reference voltage and reference current of stable level regardless of temperature variation
Document administration apparatus, document administration method and recording medium
Method and apparatus for detecting photoacoustic signal
Exhaust emission control device
Image forming apparatus with toner scattering control
Shock absorber health and condition monitoring device