Patent · US Expired

System and method for a multi-level locking hierarchy in a database with multi-dimensional clustering

US7236974B2 · kind B2 · utility

39Cited by
16References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 29, 2003
Grant dateJun 26, 2007
Priority date
Expiry dateMar 3, 2024

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S707/99939
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A multi-level locking hierarchy for a relational database includes a locking level applied to a multi-dimensionally clustering table, a locking level applied to blocks within the table, and a locking level applied to rows within the blocks. The hierarchy leverages the multi-dimensional clustering of the table data for efficiency and to reduce lock overhead. Data is normally locked in order of coarser to finer granularity to limit deadlock. When data of finer granularity is locked, data of coarser granularity containing the finer granularity data is also locked. Block lock durations may be employed to ensure that a block remains locked if any contained row remains locked. Block level lock attributes may facilitate detection of at least one of a concurrent scan and a row deletion within a block. Detection of the emptying of a block during a scan of the block may bar scan completion in that block.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.