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.

公开(公告)号：CA2426439A1

公开(公告)日：2004-10-23

申请号：CA2426439

申请日：2003-04-23

Applicant: IBM CANADA

Inventor： VAN BOESCHOTEN ROBIN D ,  SCHIEFER BERNHARD K ,  MARTIN PAT ,  ELNAFFAR SAID ,  HORMAN RANDALL W ,  LIGHTSTONE SAM S

IPC: G06F16/90 ,  G06F9/50 ,  G06F17/30 ,  G06F17/60

Abstract: Workload type to be managed by a database management system (DBMS) is a key consideration in tuning the DBMS. Allocations for resources, such as main memory, can be very different depending on whether the workload type is Online Transaction Processing (OLTP) or Decision Support System (DSS). The DBMS also experiences changes in workload type during the normal processing cycle of the DBMS. Database administrators must therefore recognize the significant shift s of workload type that demand reconfiguring the DBMS in order to maintain acceptable levels of performance. Disclosed is a workload type classifier module, used by a DBMS, for recognizing workload types so that the DBMS may then manage or adjust its performance and reconfiguring its resources accordingly. The classifier may be constructed based on the most significant workload characteristics th at differentiate OLTP from DSS; then, the classifier is used for identifying changes in workload types contained in a workload. One aspect, there is provided, for an information retrieval system, a method of identifying a workload type for a given workload, including selecting a sample of the given workload, and predicting identification of the workload type based on a comparison between the selected sample and a set of rules.