WGU C175 Data Management Foundations Study Guide , Complete Solution

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 • Processing may be as simple as organizing it to reveal patterns or complex as making forecast / drawing inferences using system statistical modeling o Key to good decision making and business survival is accurate, relevant, and timely information • Knowledge o Information and facts about a specific subject o Implies familiarity awareness and understanding of Information o Key Characteristic is that New Knowledge can be derived from Old Knowledge • Data Management o A discipline that focuses on the proper generation, storage, and retrieval of data o Is it core activity for any business, government agency, service organization, or charity 1.4 Introducing the Database • Database o Shared, integrated computer structure that stores: • End User Data o Raw facts of interest to the end user • Metadata (Also called: A collection of Self-Describing Data) o Data about data through which data is integrated and managed o Describes data characteristics and set of relationships that links data found in the database o Stores information like: • Name of each data element • Type of values (numeric, dates, or text) on each data element • Whether the data element can be left empty o Complements and expands the value and use of the data • Role of the DBMS o An intermediary between user and database o Presents the end user with a single integrated view of data in a database o Receives all application requests and translates them into complex operations o Hides database complexities from the application programs and users o Provides a framework facilitate data quality initiatives o May be written using Visual Basic, NET, JAVA, C#, or through a DBMS