Boots – shoes – and leggings
Patent
1993-02-05
1995-08-08
Black, Thomas G.
Boots, shoes, and leggings
3642468, 3642463, 3642464, 3642821, 3642823, 3642832, 364DIG1, G06F 1540
Patent
active
054407320
ABSTRACT:
A database-management system (10) generates bounded-disorder indexes on its database keys. In such an index, the leaf nodes (51, 62) are large and are divided into a number of buckets (52, 54, 56, 58), only one of which ordinarily is accessed in any given single-record database operation. The key values in a leaf node are distributed among the leaf node's buckets in accordance with a hashing function. The lockable ranges locked for scanning functions are defined in accordance with key-valued locking, in which each lockable range is bounded by successive key values that exist in the database. But the multiple-bucket accesses that would otherwise be required, because of the hash-function distribution of key values among a node's several buckets, are avoided because the lockable ranges are defined by the sequence of key values in the bucket rather than in the node. In addition to the existing key values, moreover, the buckets' key-value limits are also employed to bound lockable ranges, even if no database records contain those key-value limits. This prevents end-of-bucket insertions and deletions from needing further I/O operations in order to identify the lockable ranges that those insertions and deletions modify.
REFERENCES:
patent: 4468728 (1984-08-01), Wang
patent: 4677550 (1987-06-01), Ferguson
patent: 4774657 (1988-09-01), Anderson et al.
patent: 4914596 (1990-04-01), Levine et al.
patent: 5010478 (1991-04-01), Deran
patent: 5058002 (1991-10-01), Nakamura et al.
patent: 5089952 (1992-02-01), Bozman
patent: 5119490 (1992-06-01), Kurose
patent: 5123104 (1992-06-01), Levine et al.
patent: 5237678 (1993-08-01), Kuechler et al.
Litwin, Witold, and Lomet, David B., "The Bounded Disorder Access Method," IEEE Computer Society Press, 1986, pp. 38-48.
Lomet, David B., "A Simple Bounded Disorder File Organization with Good Performance," ACM Transactions on Database Systems, vol. 13, No. 4, Dec. 1988, pp. 525-551.
Mohan, C., "ARIES/KVL: A Key-Value Locking Method for Concurrency Control of Multiaction Transactions Operating on B-Tree Indexes," Proc. Very Large Databases Conference, Brisbane, Australia, Aug. 1990.
Mohan, C. and Levine, F., "ARIES/IM: An Efficient and High Concurrency Index Management Method Using Write-Ahead Logging," IBM Research Report RJ 6846, Aug. 1989, Almaden Research Center, San Jose, Calif.
Gray, J. N., Lorie, R. A., Putzulo, G. R., and Traiger, I. L., "Granularity of Locks and Degrees of Consistency in a Shared Data Base," IFIP Working Conference on Modeling of Data Base Management Systems, 1976, 1-29.
Green Russell J.
Lomet David B.
Black Thomas G.
Born Joseph H.
Digital Equipment Corp., Pat. Law Gr.
Johnston A. Sidney
Von Buhr Maria N.
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