ITC-212-Chapter-1-Database-Concepts-1.pdf

Mindoro State University College of Computer Studies Chapter 1: Database Concepts Prepared by: JENNIE TAMARES FERNANDO BSIT Associate Program Chairperson E-mail Address: [email protected] /jenfern...

Mindoro State University College of Computer Studies Chapter 1: Database Concepts Prepared by: JENNIE TAMARES FERNANDO BSIT Associate Program Chairperson E-mail Address: [email protected] /[email protected] Mobile Number: +639778254102/ +639985804531 ITC 212 : INFORMATION MANAGEMENT Bachelor of Science in Information Technology  College of College of Computer Computer Studies Studies  In this chapter, you will learn: ◦ The difference between data and information ◦ What a database is, the various types of databases, and why they are valuable assets for decision making ◦ The importance of database design ◦ How modern databases evolved from file systems ◦ About flaws in file system data management ◦ The main components of the database system ◦ The main functions of a database management system (DBMS) ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 2  College of College of Computer Computer Studies Studies  Data  Information  Raw facts  Produced by processing data ◦ Raw data - Not yet been processed  Reveals the meaning of data to reveal the meaning  Enables knowledge creation  Building blocks of  Should be accurate, relevant, information  Data management and timely to enable good ◦ Generation, storage, and retrieval decision making of data ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 3  College of College of Computer Computer Studies Studies  Shared, integrated computer structure that stores a collection of: ◦ End-user data - Raw facts of interest to end user ◦ Metadata: Data about data, which the end-user data are integrated and managed  Describe data characteristics and relationships  Database management system (DBMS) ◦ Collection of programs ◦ Manages the database structure ◦ Controls access to data stored in the database ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 4  College of College of Computer Computer Studies Studies  Intermediary between the user and the database  Enables data to be shared  Presents the end user with an integrated view of the data  Receives and translates application requests into operations required to fulfill the requests  Hides database’s internal complexity from the application programs and users ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 5  College of College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 6  College of College of Computer Computer Studies Studies Better data integration and less data inconsistency – Data inconsistency: Different versions of the same data appear in different places Increased end-user productivity Improved: ◦ Data sharing ◦ Data security ◦ Data access ◦ Decision making  Data quality: Promoting accuracy, validity, and timeliness of data ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 7  College of College of Computer Computer Studies Studies  Single-user database: Supports one user at a time ◦ Desktop database: Runs on PC  Multiuserdatabase: Supports multiple users at the same time ◦ Workgroup databases: Supports a small number of users or a specific department ◦ Enterprise database: Supports many users across many departments ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 8  College of College of Computer Computer Studies Studies  Centralized database: Data is located at a single site  Distributed database: Data is distributed across different sites  Cloud database: Created and maintained using cloud data services that provide defined performance measures for the database ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 9  College of College of Computer Computer Studies Studies  General-purpose databases: Contains a wide variety of data used in multiple disciplines  Discipline-specific databases: Contains data focused on specific subject areas ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 10  College of College of Computer Computer Studies Studies  Operational database: Designed to support a company’s day-to-day operations  Analytical database: Stores historical data and business metrics used exclusively for tactical or strategic decision making ◦ Data warehouse: Stores data in a format optimized for decision support ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 11  College of College of Computer Computer Studies Studies ◦Online analytical processing (OLAP)  Enable retrieving, processing, and modeling data from the data warehouse ◦Business intelligence: Captures and processes business data to generate information that support decision making ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 12  College of College of Computer Computer Studies Studies  Unstructured data: It exists in their original state  Structured data: It results from formatting ◦ Structure is applied based on type of processing to be performed  Semistructured data: Processed to some extent  Extensible Markup Language (XML) ◦ Represents data elements in textual format ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 13  College of College of Computer Computer Studies Studies  Focuses on the design of the database structure that will be used to store and manage end-user data  Well-designed database ◦ Facilitates data management ◦ Generates accurate and valuable information  Poorly designed database causes difficult-to- trace errors ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 14  College of College of Computer Computer Studies Studies Manual File Systems Accomplished through a system of file folders and filing cabinets Computerized File Systems Data processing (DP) specialist: Created a computer-based system that would track data and produce required reports File System Redux: Modern End-User Productivity Tools Includes spreadsheet programs such as Microsoft Excel ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 15  College of College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 16  College of College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 17  College of College of Computer Computer Studies Studies Lengthy development times Difficulty of getting quick answers Complex system administration Lack of security and limited data sharing Extensive programming ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 18  College of College of Computer Computer Studies Studies  Structural dependence: Access to a file is dependent on its own structure ◦ All file system programs are modified to conform to a new file structure  Structural independence: File structure is changed without affecting the application’s ability to access the data ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 19  College of College of Computer Computer Studies Studies  Data dependence ◦ Data access changes when data storage characteristics change  Data independence ◦ Data storage characteristics is changed without affecting the program’s ability to access the data  Practical significance of data dependence is difference between logical and physical format ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 20  College of College of Computer Computer Studies Studies  Unnecessarily storing same data at different places  Islands of information: Scattered data locations ◦ Increases the probability of having different versions of the same data ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 21  College of College of Computer Computer Studies Studies  Poor data security  Data inconsistency  Increased likelihood of data-entry errors when complex entries are made in different files  Data anomaly: Develops when not all of the required changes in the redundant data are made successfully ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 22  College of College of Computer Computer Studies Studies Update Anomalies Insertion Anomalies Deletion Anomalies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 23  College of College of Computer Computer Studies Studies  Evident despite the availability of multiple personal productivity tools being available  Data-modeling skills is vital in the data design process  Good data modeling facilitates communication between the designer, user, and the developer ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 24  College of College of Computer Computer Studies Studies  Logically related data stored in a single logical data repository ◦ Physically distributed among multiple storage facilities DBMS eliminates most of file system’s problems  Current generation DBMS software: – Stores data structures, relationships between structures, and access paths – Defines, stores, and manages all access paths and components ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 25  College of College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 26  College of College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 27  College of College of Computer Computer Studies Studies Data dictionary management Data dictionary: Stores definitions of the data elements and their relationships Data storage management Performance tuning: Ensures efficient performance of the database in terms of storage and access speed Data transformation and presentation Transforms entered data to conform to required data structures Security management Enforces user security and data privacy ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 28  College of College of Computer Computer Studies Studies Multiuser access control Sophisticated algorithms ensure that multiple users can access the database concurrently without compromising its integrity Backup and recovery management Enables recovery of the database after a failure Data integrity management Minimizes redundancy and maximizes consistency ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 29  College of College of Computer Computer Studies Studies Database access languages and application programming interfaces Query language: Lets the user specify what must be done without having to specify how Structured Query Language (SQL): De facto query language and data access standard supported by the majority of DBMS vendors Database communication interfaces Accept end-user requests via multiple, different network environments ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 30  College of College of Computer Computer Studies Studies Increased costs Management complexity Maintaining currency Vendor dependence Frequent upgrade/replacement cycles ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS 31  College of 32 College of Computer Computer Studies Studies ITC 212 : INFORMATION MANAGEMENT TOPIC: DATABASE CONCEPTS