A Deterministic Model for Semistructured and Structured Data

半结构化和结构化数据的确定性模型

• 批准号: 9977408
• 负责人: Susan Davidson
• 金额: $ 25.5万
• 依托单位: University of Pennsylvania
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1999
• 资助国家: 美国
• 起止时间: 1999-10-01 至 2003-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9977408&HistoricalAwards=false
• 关键词: Deterministic; Model; Semistructured; Structured; Data

With the development of the Internet, databases are being copied, transformed, and corrected on an unprecedented scale. With this comes the need to annotate data: for correcting it, commenting on it, or for recording its provenance. However, conventional databases have a regular structure and provide no "room" for annotations which are typically irregular and required at all levels of granularity. Annotations require some form of semistructured representation. This investigation centers on a new model for structured and semistructured data which is intended to facilitate the process of data annotation. The usual models of semistructured data are based on an edge-labeled graph and are "nondeterministic" in that a given vertex may have several out-edges with the same label. The model proposed here is more restrictive in that these labels must all be different. It is less restrictive because the labels themselves may themselves carry data. In fact a label may itself be a small piece of semistructured data. A number of advantages are claimed for this model. Like XML, the data representation is entirely syntactic. All operations are syntactic,, and serialization of data is immediate. Object identifiers in particular are syntactic constructs, they have structure, and certain database transformations may be achieved by manipulation of this structure. The goal of the investigation is to develop the model and associated interfaces so that it can be used as a common representation for both semistructured and structured data. A second goal is to develop tools for data annotation. http://db.cis.upenn.edu/Research/

随着互联网的开发，数据库正在以空前的规模复制，转换和纠正。随之而来的是需要注释数据：纠正数据，对其进行评论或记录其出处。但是，常规数据库具有规则的结构，并且没有为通常不规则且在各个粒度所需的注释提供“空间”。注释需要某种形式的半结构表示。该调查集中在一个新的模型和半结构化数据的新模型上，该模型旨在促进数据注释过程。半结构数据的通常模型基于边缘标记的图，并且是“非确定性”的，因为给定的顶点可能具有具有相同标签的几个外边缘。这里提出的模型更具限制性，因为这些标签必须不同。这是不太限制的，因为标签本身可能携带数据。实际上，标签本身可能是一小部分半结构化数据。对于此模型，声称有许多优势。像XML一样，数据表示完全是句法。所有操作都是句法，数据的序列化是直接的。尤其是对象标识符是句法结构，它们具有结构，并且可以通过操纵该结构来实现某些数据库转换。调查的目的是开发模型和相关的接口，以便它可以用作半结构和结构化数据的共同表示。第二个目标是开发用于数据注释的工具。 http://db.cis.upenn.edu/research/