WGU C175 Data Management Foundations Study Guide

14% Lesson 1 Introduction to Databases, Information and Data (7 Questions) Competency 4017.1.1: Introduction to Information and Data Explain how data, databases, and data management is used in today's organization Explain what data is and how is it stored Explain the different types of data Define file structures Explain how data was stored and retrieved before the use of database management systems 1.1 Why Databases • Best way to store and manage data • Makes data persistent and shareable in a secure way • Essential for organizations to know information about Customers, Products, Employees, Debtors / Creditors • Helps organizations use data / information as a resource to make decisions 1.2 File Structures • File-Based (Prior to DBMS) o Attempt to computerize old manual filing system o Was easy to retrieve small amounts of information from o As data grew, it became difficult to locate and retrieve information o Retrieval speed depended on file structure and how data was organized within the structure • File types utilized in a file-based system o Flat Files • No internal hierarchy • Plain text or Binary files • Data that is unstructured • Uses a lot of computer memory to access, edit, and rewrite files after use o Heap Files • Unsorted set of records • Uniquely identified by record ID o Allows Heap file to be inserted or deleted using ID o Index Files • File that stores a list of Look Up Field values from data file that includes the location (address) in the data file of the corresponding record • Smaller than the entire record, usually fits in main memory for quick look up • Lists keywords and phrases that are in a particular file • Becomes a pointer to the location in the file where the information can be found when stored with keywords and phrases o Hashed Files • Uses hash functions to decide where records should be placed on a disk • Allows for faster data look up without the use of an index file 1.3 Data versus Information • Data o Data is the Foundation of Information o Consists of Raw Facts not yet processed to reveal meaning o Raw facts / data will need to be transformed to better understand what it is that you have o Must be properly formatted for storage, processing, and presentation • Information o Information is the Bedrock of Knowledge o Produced by Processing Raw Data to reveal its meaning