Patents by Inventor Douglas S. Boa

Douglas S. Boa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method and apparatus for finding nearest logical record in a hash table
    Patent number: 6957216
    Abstract: A method, apparatus, software and data structure is disclosed for more efficient access times for linear operations in a hash table, including finding the nearest logical record. A plurality of actual data records and a plurality of marker data records are inserted in a hash table using a hash function. The actual data records and marker data records have a logical ordering specified by a key and are threaded into the hash table to allow linear access by walking the hash table. The logical ordering of the actual data records and marker records is lost upon entry into the hash table, and the keys of the marker data records are distributed at known positions throughout the range of the keys of the actual data records. If when hashing a given key no record exists in the database for the given key, one of the keys for the marker data records are hashed to locate the associated marker data record in the hash table.
    Type: Grant
    Filed: September 16, 2002
    Date of Patent: October 18, 2005
    Assignee: Microsoft Corporation
    Inventors: Douglas S. Boa, Simon M. Meacham, Barry M. Nolte
  • Method and apparatus for marking a hash table and using the marking for determining the distribution of records and for tuning
    Patent number: 6560599
    Abstract: A method, apparatus, software and data structure is disclosed for more efficient access times for linear operations in a hash table. A plurality of actual data records and a plurality of marker data records are inserted in a hash table using a hash function. The actual data records and marker data records have a logical ordering specified by a key and are threaded into the hash table to allow linear access by walking the hash table. The logical ordering of the actual data records and marker records is lost upon entry into the hash table, and the keys of the marker data records are distributed at known positions throughout the range of the keys of the actual data records. If when hashing a given key no record exists in the database for the given key, one of the keys for the marker data records are hashed to locate the associated marker data record in the hash table.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: May 6, 2003
    Assignee: Microsoft Corporation
    Inventors: Douglas S. Boa, Simon M. Meacham, Barry M. Nolte
  • Method and apparatus for finding nearest logical record in a hash table
    Publication number: 20030028547
    Abstract: A method, apparatus, software and data structure is disclosed for more efficient access times for linear operations in a hash table, including finding the nearest logical record. A plurality of actual data records and a plurality of marker data records are inserted in a hash table using a hash function. The actual data records and marker data records have a logical ordering specified by a key and are threaded into the hash table to allow linear access by walking the hash table. The logical ordering of the actual data records and marker records is lost upon entry into the hash table, and the keys of the marker data records are distributed at known positions throughout the range of the keys of the actual data records. If when hashing a given key no record exists in the database for the given key, one of the keys for the marker data records are hashed to locate the associated marker data record in the hash table.
    Type: Application
    Filed: September 16, 2002
    Publication date: February 6, 2003
    Applicant: Microsoft Corporation
    Inventors: Douglas S. Boa, Simon M. Meacham, Barry M. Nolte
  • Method and apparatus for finding nearest logical record in a hash table
    Patent number: 6480858
    Abstract: A method, apparatus, software and data structure is disclosed for more efficient access times for linear operations in a hash table, including finding the nearest logical record. A plurality of actual data records and a plurality of marker data records are inserted in a hash table using a hash function. The actual data records and marker data records have a logical ordering specified by a key and are threaded into the hash table to allow linear access by walking the hash table. The logical ordering of the actual data records and marker records is lost upon entry into the hash table, and the keys of the marker data records are distributed at known positions throughout the range of the keys of the actual data records. If when hashing a given key no record exists in the database for the given key, one of the keys for the marker data records are hashed to locate the associated marker data record in the hash table.
    Type: Grant
    Filed: June 30, 1999
    Date of Patent: November 12, 2002
    Assignee: Microsoft Corporation
    Inventors: Douglas S. Boa, Simon M. Meacham, Barry M. Nolte