Databases
Assignment 3: Databases Due Week 7 and worth 110 points You are the trainer for a major technology firm. One of the problems your firm has is hiring new technologists who have a fundamental understanding of relational databases. Therefore, you’ve been asked to create a database orientation paper. Write a four to five (4-5) page paper in which you: 1. Describe what a relational database is and why relational databases are needed. 2. Describe the process of normalization and why it is needed. 3. Contrast and compare logical and physical database design. 4. Critique SQL as a user-friendly query language. 5. Use at least three (3) quality resources in this assignment. Note: Wikipedia and similar Websites do not qualify as quality resources. Your assignment must follow these formatting requirements: Be typed, double-spaced, using Times New Roman font (size 12), with one-inch margins on all sides; citations and references must follow APA or school-specific format. Check with your professor for any additional instructions. Include a cover page containing the title of the assignment, the student’s name, the professor’s name, the course title, and the date. The cover page and the reference page are not included in the required assignment page length.
Name:
Institution:
Date:
Introduction
Having a properly designed database is important if accurate information is to be provided to an organization. Initial creation of an effective database ensures that modifications to this initial design will be kept at minimum. Discovering problems after putting into operation, a particular database may turn out to be detrimental to the institution, business, or organization. Database development is a three-phase process that is first logical design that involves the definition of fields, tables, foreign and primary keys, establishment of relationships between tables, and levels of integrity of data. Second is implementation of the logical design using Data Base Management Systems (DMBS) to create tables and how their relationships and using the tools to implement levels of integrity for the data. Finally, is the development of an application for end users.
Q.1
What is a Relational Database?
Databases contain one or more tables of information. The tables contain rows and columns the rows are called records while the columns are referred to as fields or attributes. Databases having one table are called flat databases while a database with two or more related table is a relational database. Therefore, a relational database is a database having symbols that are organized into a collection of relationships (Date, 2012). Dr. Codd applied theories used first order predicate logic theory and the set theory in designing relational databases. Relationship here is, therefore, relation is a formal term used in the logical foundations of mathematics and appeals to the notion of two things being related (Date, 2012).
Figure 1: Relational Database
Source: IGCSE ICT-Types of Database (dineshibakshi.com)
Why are Relational Databases Needed?
Big data has been a problem for most institutions and organizations with the trend in big data indicating a shift towards a point where organizations will be handling and extracting information from databases that are growing to the multi-petabyte range. These large amounts of data have pushed developers towards finding methods that can handle such amounts of data. The choice of an effective database management system is based on the environment where the system will be used, the volume of data, and the needs of the organization and particular application.
Relational databases are needed as they can process ad-hoc queries. Applications for production may at times require primary key lock-ups only while reporting queries often require filter or aggregates that are based on other columns. Databases for documents and distributed key value stores sometimes support these only when and index on the relevant column is clearly defined and where is it does not it may not support such an index. In addition, relational databases are mature and tested technology. Relational databases have been in existence for over 10 years and have stable code bases. These databases are relatively bug-free and their causes of failure known and can be easily be handled. When used by experienced Database Analysts (DBAs) they can apply the relevant techniques to maximize its uptime and in case of failure guarantee recovery of data (Silberschatz, Korth, & Sudarsh, 2011).
Moreover, relational databases support SQL an easy human-readable language. The instructions in SQL are plain and can be put to relational databases for implementation. In addition, most vendors for databases support SQL standards. When used in relational databases they provide its users with simple process of operation to manipulate data. Relational databases provide defined relationships between tables hence provide a complete picture of the data (Silberschatz, Korth, & Sudarsh, 2011). Finally, relational databases are based on relational set theory. In the relational model of databases, normalization is critical, the relational databases support these operations and they work best with normalized tables. Therefore, relational databases support relational algebra and the relational set theory. The database also supports mathematical set operations and select, ...