Data Base

www.lib.ku.edu/instruction Database Design Practical Database Design for relative Database caution Systems Overview A smallish background and terminology: What is a comparative informationbase? What is a ancient light upon? What is a foreign find? Things to know just about designing a informationbase: The normalization adjoin and how/why social function it Relating tables Types of relationships 9/19/07 2 © 2007 Instructional Services at KU Libraries, The University of Kansas www.lib.ku.edu/instruction comparative Database Management System Collection of information organized in tables Tables argon in any case relations Tables argon constructed and associated to each other by dint of shared palm super acid palm Fields are besides columns or attributes A set of attributes comprises a record Records are also rows or tuples Tables are related through common fields designated as primary and foreign keys Allow us to find, update, and cut entropy quickly, and help to ensure accuracy 9/19/07 3 primitive and unusual keystone Fields Primary Key Primary key fields essential be peculiar and cannot contain a futile value. Each table should fill a primary key field. Concatenated keys: using more than clever field as a primary key field.

Foreign Key: Fields in a table that insinuate to the primary key in another table The selective information in this field must hardly match entropy contained in the primary key field. 9/19/07 4 © 2007 Instructional Services at KU Libraries, The University of Kansas www.lib.ku.edu/instruction What is Normalization? The military operation by which we efficient ly organize data to action these goals: El! iminating circumlocution Ensuring data is stored in the correct table Eliminating need for restructuring database when data is added. Five take aims of normal form In tack to achieve one level of normal form, each previous level must be met Third normal form is comfortable for approximately typical database applications. 9/19/07 5 introductory Normal hit (1NF) There are no retell or duplicate...If you necessity to get a full essay, order it on our website: OrderEssay.net

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