外文翻譯---關(guān)系數(shù)據(jù)庫(kù)的結(jié)構(gòu)-數(shù)據(jù)庫(kù)(已修改)
2025-06-01 10:37 本頁(yè)面
【正文】 ┊┊┊┊┊┊┊┊┊┊┊┊┊裝┊┊┊┊┊訂┊┊┊┊┊線┊┊┊┊┊┊┊┊┊┊┊┊┊安徽工業(yè)大學(xué)工商學(xué)院 畢業(yè)設(shè)計(jì)（論文）說(shuō)明書(shū)附錄二：英漢翻譯一、英文原文Structure of the Relational database—《Database System Concepts》Part1: Relational DatabasesThe relational model is the basis for any relational database management system (RDBMS).A relational model has three core ponents: a collection of objects or relations, operators that act on the objects or relations, and data integrity methods. In other words, it has a place to store the data, a way to create and retrieve the data, and a way to make sure that the data is logically consistent.A relational database uses relations, or twodimensional tables, to store the information needed to support a business. Let39。s go over the basic ponents of a traditional relational database system and look at how a relational database is designed. Once you have a solid understanding of what rows, columns, tables, and relationships are, you39。ll be well on your way to leveraging the power of a relational database.Tables, Row, and ColumnsA table in a relational database, alternatively known as a relation, is a twodimensional structure used to hold related information. A database consists of one or more related tables.Note: Don39。t confuse a relation with relationships. A relation is essentially a table, and a relationship is a way to correlate, join, or associate two tables.A row in a table is a collection or instance of one thing, such as one employee or one line item on an invoice. A column contains all the information of a single type, and the piece of data at the intersection of a row and a column, a field, is the smallest piece of information that can be retrieved with the database39。s query language. For example, a table with information about employees might have a column called LAST_NAME that contains all of the employees39。 last names. Data is retrieved from a table by filtering on both the row and the column.Primary Keys, Datatypes, and Foreign KeysThe examples throughout this article will focus on the hypothetical work of Scott Smith, database developer and entrepreneur. He just started a new widget pany and wants to implement a few of the basic business functions using the relational database to manage his Human Resources (HR) department.Relation: A twodimensional structure used to hold related information, also known as a table.Note: Most of Scott39。s employees were hired away from one of his previous employers, some of whom have over 20 years of experience in the field. As a hiring incentive, Scott has agreed to keep the new employees39。 original hire date in the new database.Row:A group of one or more data elements in a database table that describes a person, place, or thing.Column:The ponent of a database table that contains all of the data of the
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