Adata modelis anabstract modelthat organizes elements ofdataand standardizes how they relate to one another and to the properties of real-world entities.。 —https://en.wikipedia.org/wiki/Data_model 数据模型:如何组织数据,如何标准化关系,如何关联现实。 它既决定了我们构建软件的方式(实现),也左右了...
Martin, G., Gordon, T. 1977, Data-Base Management Systems Data Models and Query Languages, Computers and Geosciences 3, 387–393.Martin, G., and T. Gordon, 1977, Data-base management systems -- data models and query languages: Computers & Geo- sciences, v. 3, no. 3, p. 387-394....
Chapter 2 :Data Models and Query Languages 关系型模型(Relational Model) VS 文件型模型(Document Model) 关系型模型典型的例子就是关系型数据库,通过 SQL 语言来进行数据查询。 NoSQL的诞生 NoSQL 意为 Not Only SQL,其流行背后的原因有: 比关系型数据库更好的扩展性,基于超大规模数据或者非常高的吞吐量要求...
Data-base management systems support three types of data model—hierarchic, network, and relational. Query facilities range from high-level, nonprocedural languages to host-language, coded procedures. Evaluation of DBMS for geoscience applications requires careful consideration of both these features.Access...
Data models and query languages for spatial databases The main purpose of this paper is to investigate the characteristics that distinguish spatial databases systems from traditional ones. Hereto, we give an o... J Paredaens,B Kuijpers - 《Data & Knowledge Engineering》 被引量: 75发表: 1998年...
In the first step, we formally specify the syntax and semantics of SQL++, a unifying semi-structured data model and query language that encompasses the data models and query languages of the surveyed databases. Then, we present fifteen feature matrices (and additional analysis) that classify each...
in Computer Science programs. This book can be used to supplement any main text for the introductory database systems course. This invaluable learning tool provides an understanding of the industry-standard query language SQL. Using an appropriate mix of underlying mathematical formalism and hands......
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Data Science Dojo blog features the most recent, and relevant articles about data science, analytics, generative AI, large language models, machine learning, and data visualization.
Data models and query languages designed for well structured data are inappropriate in such environments. Starting with a "lightweight" object model adopted ... D Quass,A Rajaraman,J Ullman,... - 《Journal of Systems Integration》 被引量: 313发表: 1997年 A meta-analysis of randomized controll...