Patent ID: 6618729
Filing Date: 2003-09-09
Classification: G06F,Y10S

Abstract:
A method of performing a star join in a computer to retrieve data from a relational database stored in one or more data storage devices coupled to the computer, the method comprising:(a) generating a cross-product from a plurality of dimension tables referenced by the star join; (b) hashing one or more join columns of the cross-product to create a hash-row value; (c) using the hash-row value to probe a Star Map to determine whether a record exists in the fact table that corresponds to the cross-product, wherein a fist portion of the hash-row value is used to select a row of the Star Map, a second portion of the hash-row value is used to select a column of the selected row of the Star Map, and a value stored at the selected row and column of the Star Map indicates whether the record ay exist in the fact table that corresponds to the cross-product; and (d) accessing the fact table to perform a join with the cross-product when the selected column of the selected row of the Star Map indicates that the record may exist in the fact table.