Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
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
Semiconductor memory device
Image scanner and image forming apparatus
Process for making thermoplastic polymer pellets
Power-on reset circuit
Transport of multiple asynchronous data streams using higher order modulation
Cardiopulmonary resuscitation monitoring apparatus
Aperture stop
  Randomly Featured Patents
Automatic spray apparatus for oily confectionery raw material
Environmentally degradable urns for burial of human cremation ashes in terrestrial cemeteries
Non-insulated printed circuit jack with retaining feature
Image reading apparatus
Hair dryer and attachment system
Saw shifting apparatus
Direct current power unit
Compact thermoelectric refrigerator and module
Mower presence control assembly including a ribbon switch
Uniform dispensing, multi-chambered tube comprising a flow regulating element