The relational database model

In this study, an artificial neural networkbased Bayesian regularization (ANN) model is proposed to predict the compressive strength of concrete. The database in this study includes 208 experimental results synthesized from laboratory experiments with 9 input variables related to temperature change and design material composition.

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The main contents of the chapter consist of the following: Function M-files, syntax of function M-Files, comments, multiple input and output functions, relational model concepts, relational model constraints and relational database schemas, update operations and dealing with constraint violations.

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In this paper, we propose a new approach to overcome the limitations of the approach that is based on hedge algebra structure for building fuzzy object-oriented databases model. Some operators fuzzy object-oriented relation algebra are proposed corresponding with the model. Finally,we propose a method of fuzzy object-oriented query processing flexibly.

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The report proposes the concept of positive boolean dependency in the database model of block form, proving equivalent theorem of three derived types, necessary and sufficient criteria of the derived type, the member problem... In addition, some properties related to this concept in the case of block r degenerated into relation are also expressed and demonstrated here.

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This paper introduces a probabilistic relational database model, called PRDB, for representing and querying uncertain information of objects in practice. To develop the PRDB model, first, we represent the relational attribute value as a pair of probabilistic distributions on a set for modeling the possibility that the attribute can take one of the values of the set with a probability belonging to the interval which is inferred from the pair of probabilistic distributions

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Chapter 2 - The relational model. In this chapter students will be able to: Learn the conceptual foundation of the relational model, understand how relations differ from nonrelational tables, learn basic relational terminology, learn the meaning and importance of keys, foreign keys, and related terminology, understand how foreign keys represent relationships.

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Learning objectives of this chapter include: Learn how to transform E-R data models into relational designs; practice the normalization process from chapter 2; understand the need for denormalization, learn how to represent weak entities with the relational model; know how to represent 1:1, 1:N, and N:M binary relationships.

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Bài giảng "Cơ sở dữ liệu - Chương 3: Mô hình dữ liệu quan hệ" cung cấp cho người đọc các kiến thức: Quá trình thiết kế CSDL, quan hệ (Relation), thuộc tính (Attribute), lược đồ (relation schema), kiểu dữ liệu và miền giá trị (Domain),... Mời các bạn cùng tham khảo nội dung chi tiết.

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In this chapter, The contents concentrate on describing the basic principles of the relational model of data, begin by defining the modeling concepts and notation of the relational model, discussion of relational constraints that are considered an important part of the relational model and are automatically enforced in most relational DBMSs, defines the update operations of the relational model,...

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Chapter 7 discusses how to design a relational database schema based on a conceptual schema design. This chapter presented a high-level view of the database design process, and in this chapter we focus on the logical database design or data model mapping step of database design. We present the procedures to create a relational schema from an Entity-Relationship (ER) or an Enhanced ER (EER) schema.

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In this chapter we discuss the two formal languages for the relational model: the relational algebra and the relational calculus. The main contents in this chapter include: Example database application (COMPANY), overview of the QBE language (appendix D),...

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Bài giảng Chương 2: Mô hình cơ sở dữ liệu quan hệ (The Relational Database Model) bao gồm những nội dung về khái niệm, quan hệ, quan hệ và bảng, thuộc tính, bộ và quan hệ, lược đồ quan hệ, các phép toán, đại số quan hệ, ràng buộc toàn vẹn.

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The relational Model of Data is based on the concept of a Relation. A Relation is a mathematical concept based on the ideas of sets. The strength of the relational approach to data management comes from the formal foundation provided by the theory of relations. We review the essentials of the relational approach in this chapter.

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Data Model: A set of concepts to describe the structure of a database, and certain constraints that the database should obey. Data Model Operations: Operations for specifying database retrievals and updates by referring to the concepts of the data model. Operations on the data model may include basic operations and user-defined operations.

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The minimum number of Cs that can be associated with one A is 1. I know this because the existence of the C to A relationship is mandatory. The maximum number of Cs that can be associated with one A is unlimited (or many). I know this because the cardinality of the C to A relationship is 1-M.

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Câu 1: A problem soling technique that decomposes a system its component parts while focusing on the business problem independent of technology is: a. Cause-and-effect analysis. b. System design. c. Joint application design(JAD). d. Systems analysis. Câu 2: A database is an organized collection of ____ related data. a. None of the others answers. b. logically. c. not. d. physically.

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Beginning Database Design- P25:This book focuses on the relational database model from a beginning perspective. The title is, therefore, Beginning Database Design. A database is a repository for data. In other words, you can store lots of information in a database. A relational database is a special type of database using structures called tables. Tables are linked together using what are called relationships. You can build tables with relationships between those tables, not only to organize your data, but also to allow later retrieval of information from the database....

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Beginning Database Design- P24:This book focuses on the relational database model from a beginning perspective. The title is, therefore, Beginning Database Design. A database is a repository for data. In other words, you can store lots of information in a database. A relational database is a special type of database using structures called tables. Tables are linked together using what are called relationships. You can build tables with relationships between those tables, not only to organize your data, but also to allow later retrieval of information from the database....

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Beginning Database Design- P23:This book focuses on the relational database model from a beginning perspective. The title is, therefore, Beginning Database Design. A database is a repository for data. In other words, you can store lots of information in a database. A relational database is a special type of database using structures called tables. Tables are linked together using what are called relationships. You can build tables with relationships between those tables, not only to organize your data, but also to allow later retrieval of information from the database....

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Beginning Database Design- P22:This book focuses on the relational database model from a beginning perspective. The title is, therefore, Beginning Database Design. A database is a repository for data. In other words, you can store lots of information in a database. A relational database is a special type of database using structures called tables. Tables are linked together using what are called relationships. You can build tables with relationships between those tables, not only to organize your data, but also to allow later retrieval of information from the database....

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