×

Data base optimizer using most frequency values statistics

  • US 4,956,774 A
  • Filed: 09/02/1988
  • Issued: 09/11/1990
  • Est. Priority Date: 09/02/1988
  • Status: Expired due to Fees
First Claim
Patent Images

1. In a method for accessing data of a relational data base management system having at least one index, the improvement characterized by the steps performed by a computer of:

  • (a) selecting a number of most frequently occurring values of at least part of a key of the index, the number being greater than zero and less than a total number of such values;

    (b) collecting frequency of occurrence statistics for the selected most frequently occurring values of the index;

    (c) estimating a time required for using the index as the access path, based at least in part on the collected frequency of occurrence statistics;

    (d) selecting an access path based at least in part on the estimated time; and

    (e) accessing the data using the selected access path.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×