III-COR: Collaborative Research: Graceful Evolution and Historical Queries in Information Systems-- a Unified Approach

III-COR：协作研究：信息系统中的优雅演化和历史查询——统一方法 数据库模式演化代表信息系统生命周期中的一个常数，并且是维护、升级和服务停机的主要成本的来源。传统的模式修订过程取决于新模式的安装以及修订后的数据库以及一组转换后的应用程序（为使用此模式而费力地重写）。相反，该项目开发了新颖的支持技术，从而将模式演化问题简化为协调模式、应用程序和数据库的多个并发版本之间的映射。这是通过 Meta-Manager 系统实现的，该系统提供对不断演变的 (i) 数据和 (ii) 元数据的集成管理，并有效地支持优雅模式演变所需的 (iii) 映射和 (iv) 软件工件。此外，元管理器允许保存和查询数据库历史记录，同时帮助用户规划如何通过“假设”演进场景来演进当前模式版本。该系统的功能和性能通过各种测试台进行验证，例如圣地亚哥超级计算中心的存储请求代理，该代理为从天体物理学家到生物学家等各个研究小组托管科学数据。这种新颖而及时的方法为信息系统的演变和保存提供了统一的解决方案。由于信息系统发挥着关键作用，广泛的科学、教育和经济活动将从这些进步中受益。结果通过项目网站上的出版物、报告和演示进行传播： http://www.cs.ucr.edu/~tsotras/meta-manager http://wis.cs.ucla.edu/projects/meta-manager http://db.ucsd.edu/people/alin/meta-manager

III-COR: Collaborative Research: Graceful Evolution and Historical Queries in Information Systems-- a Unified Approach Database schema evolution represents a constant in the life cycle of Information Systems, and is the source of major costs for maintenance, upgrading, and service down time. The traditional schema revision process depends on the installation of a new schema along with the revised database, and a converted set of applications (laboriously rewritten to work with this schema). Instead, this project develops the novel enabling technology whereby the schema evolution problem is reduced to coordinating mappings between multiple concurrent versions of the schema, applications, and the database. This is realized by the Meta-Manager system which provides integrated management of evolving (i) data, and (ii) metadata, and efficiently supports the (iii) mappings, and (iv) software artifacts needed for graceful schema evolution. Further, the Meta-Manager allows for preservation and querying of database history while it assists the user in planning how to evolve the current schema version with ``what-if'' evolution scenarios. The functionality and performance of the system is validated using various testbeds, such as, the San Diego Supercomputing Center's Storage Request Broker, which hosts scientific data for various research groups ranging from astrophysicists to biologists. This novel and timely approach provides a unified solution to both the evolution and preservation of information systems. Because of the key role played by information systems, a broad range of scientific, educational, and economic activities will benefit from these advances. Results are disseminated via publications, reports and demos available from the project web sites: http://www.cs.ucr.edu/~tsotras/meta-manager http://wis.cs.ucla.edu/projects/meta-manager http://db.ucsd.edu/people/alin/meta-manager