Access Methods for Multiversion Data

多版本数据的访问方法

• 批准号: 8815707
• 负责人: Betty Salzberg
• 金额: $ 11.61万
• 依托单位: Northeastern University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1988
• 资助国家: 美国
• 起止时间: 1988-11-15 至 1991-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=8815707&HistoricalAwards=false
• 关键词: Access; Methods; Multiversion; Data

The Time-Split B-tree is a system of data retrieval which takes advantage of the best aspects of two storage mediums: cheap, sturdy, non-erasable, but slow-access optical disk storage and more expensive but faster-access magnetic disk storage. This is accomplished by placing recent versions of data on magnetic disk where it can be updated quickly and incrementally moving older data to the slower optical disk as it matures. In addition, keeping all versions of data takes the place of a log and makes recovery simple. The principal investigator plans to analyze, refine and extend the Time-Split B-tree by: parameterizing space utilization on both mediums to improve performance for an expected use pattern; providing support for several kinds of temporal semantics; comparing with other proposed methods for using both mediums; providing support for large hierarchical versioned objects; allowing intermediate versions of records to be discarded; and, consolidating current (magnetic disk) data when old versions are migrated to optical disk. The research will contribute to the understanding of the interaction between access methods, transaction processing, temporal semantics, versioning and the interplay of storage mediums with different characteristics.

时间分割B树是一种数据检索系统， 两种存储介质的最佳方面的优点：便宜，坚固， 不可擦除，但访问速度慢的光盘存储等 昂贵但存取速度更快的磁盘存储器。 这是 通过将最新版本的数据放在磁盘上来完成 可以快速更新并逐步移动旧数据 到较慢的光盘，因为它成熟。 此外，保持所有 数据版本取代日志，使恢复变得简单。 首席研究员计划分析，完善和扩展 时间分割B树：参数化两个节点上的空间利用率 改进预期使用模式的性能的媒介; 支持多种时态语义，比较 与使用这两种介质的其他提出的方法;提供 支持大型分层版本化对象;允许 将被丢弃的记录的中间版本;以及， 合并当前（磁盘）数据时，旧版本 迁移到光盘。 这项研究将有助于 理解访问方法、事务 处理、时态语义、版本控制以及 存储介质具有不同的特性。