公开(公告)号：CA2299553A1

公开(公告)日：2001-08-25

申请号：CA2299553

申请日：2000-02-25

Applicant: IBM CANADA

Inventor： GRYZ JAREK ,  MILLER RENEE J ,  EDMONDS JEFF ,  SCHIEFER BERNHARD K

IPC: G06F17/16 ,  G06F17/00 ,  G06F7/00 ,  G06F17/30

Abstract: Determining maximal empty rectangles in a binary matrix includes building values in a staircase data structure for each successive entry in the matrix. The values in the staircase data structure are removed where the values correspond to maximal rectangles having the successive entry in the bottom right corner of the rectangle. The values in the staircase data structure for each successive entry being determinable from values in the staircase data structure for a preceding entry in the matrix. The maximal empty rectangles providing a basis for generating efficient relational join operations on defined relational tables.