Database Design Paper “A database is a structured collection of records or data that is stored in a computer system. In order for a database to be truly functional‚ it must not only store large amounts of records well‚ but be accessed easily. In addition‚ new information and changes should also be fairly easy to input.” (tech-faq.com); to ensure usefulness over the long-term‚ databases should be built with high data integrity and the ability to recover data if the hardware fails. Information that
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Relational Database Design By Paul Litwin This paper was part of a presentation at a Microsoft TechEd conference in the mid-1990s. It was adapted from Microsoft Access 2 Developer’s Handbook‚ Sybex 1994‚ by Ken Getz‚ Paul Litwin and Greg Reddick. Reprinted with permission of the publisher. While the paper uses Microsoft Access (version 2) for the examples‚ the vast majority of the discussion applies to any database and holds up pretty well over 11 years after it was written. Overview Database design
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NORMALIZATION OF DATABASE NORMALIZATION- is the process for evaluating and correcting table structures to minimize data redundancies‚ thereby‚ reducing the livelihood of data anomalies. The normalization process involves assigning attributes to tables based on the concept of determination. Normalization works through a series of stages called normal forms. 3 Stages of Normalization 1. 1NF or FIRST NORMALIZATION FORM 2. 2NF or SECOND NORMALIZATION FORM 3. 3NF or THIRED NORMALIZATION
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Normalization Normalization is a method for organizing data elements in a database into tables. Normalization Avoids • Duplication of Data – The same data is listed in multiple lines of the database • Insert Anomaly – A record about an entity cannot be inserted into the table without first inserting information about another entity – Cannot enter a customer without a sales order • Delete Anomaly – A record cannot be deleted without deleting a record about a related entity.
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Database Design Scenario Currently a school uses a non-computerised database system to store the following information about its students: roll class‚ surname‚ first name‚ guardian ’s name‚ address‚ student ’s date of birth‚ gender‚ sport house‚ emergency-contact telephone number‚ mailing name‚ list of subjects offered‚ and subjects in which the student is enrolled. The system takes up a large amount of space‚ has many duplicated entries some of these with mistakes and it is time consuming
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Part 1 Background Chapter 1 Introduction to Databases 1.1 A database management system provides a number of facilities that will vary from system to system. Describe the type of facilities you might expect‚ especially those that aid the initial implementation of a database and its subsequent administration. Initially‚ the type of facilities expected should be described. These include: data storage and retrieval‚ concurrency control mechanism‚ authorization services‚ integrity mechanisms
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ACSG 552 – 01. Processor Florence Appel Advanced Database Class- Spring 2009. Assignment #01. Friday‚ January 23‚ 2009 Due in class on Thursday‚ Jan. 22. o Chapter 2 ▪ Review Questions‚ pp. 54-55: 2‚ 5‚ 6‚ 9‚ 18‚ 19 ▪ Problems‚ pp. 55-59: 1‚ 2; 12-15; 19-21; 22; 25abcde Chapter 02: Review Questions: pp. 54-55. #02) What is a business rule‚ and what is its purpose in data modeling? The business rule is a brief‚ precise and ambiguous
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MODULE: DATABASE DESIGN & DEVELOPMENT ASSIGNMENT TITLE: VETERINARY SURGERY DATABASE DEVELOPMENT Table of Content Task 1 Page 2 Task 2 Page 5 Task 3 Page 14 Task 4 Page 28 Task 5 Page 30 Reference Page 32 Bibliography Page 33 Task 1 Question: AIM: Draw an Entity Relationship Data Model that describes the content and structure of the data held by Petcare. Specify the cardinality ratio and participation constraint of each relationship type. Answer: I have prepared this assignment
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Files and Relational Databases What is a file? • contains groups of records used to provide information for operations‚ planning‚ management and decision making. • can be used for storing data for an indefinite period of time‚ or they can be used to store data temporarily for a specific purpose. FILE TYPES • Master Files -- contain records for a group of entities. The attributes may be updated often‚ but the records themselves are relatively permanent. These files
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Benefits of a Database and Information-Gathering Techniques Brian Morrow Professor Cohen CIS 111 May 5‚ 2013 A database management system is a system in which data is stored‚ processed‚ and retrieved. These systems are known for security accuracy and consistency. A well-planned and developed database is very efficient and meets the current and future needs of the organization to which it services. This type of system allows the organization to collectively store and manipulate data. One key
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