Data Management Foundations Study Guide C175

Data Management Foundations Study Guide C175 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 1 Data Management Foundations Study Guide C175 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