L2 Database Systems: Concepts and Management - PDF

Lesson 2 Database Systems Prepared by: Prof. Era Marie Fermil Gannaban Learning Outcomes In this lesson you will learn about: 1. Define the difference between data and information 2. Describe the database. 3. Identify types of databases 4. Explain the importance of database 5....

Lesson 2 Database Systems Prepared by: Prof. Era Marie Fermil Gannaban Learning Outcomes In this lesson you will learn about: 1. Define the difference between data and information 2. Describe the database. 3. Identify types of databases 4. Explain the importance of database 5. Identify components of database system 6. Describe function of a database management system Nature of Databases Why database? From birth to death, there is a generation of data. The trail starts with the birth certificate and continues all the way to death certificate. Databases are the best way to store and manage data. Databases make data persistent and shareable in a secure way. Data vs Information Data consists of raw facts. Raw means that the data have not yet been processed. No meaning Data vs Information Information is the result of processing raw data to reveal its meaning. Data Processing is the organizing of data to reveal patterns, forecasting or drawing inferences using statistical model. Key points Data constitutes the building blocks of information. Information is produced by processing data. Information is used to reveal the meaning of data. Accurate, relevant, and timely information is the key to good decision making. Good decision making is the key to organizational survival in a global environment. Data Management Smart Phone Tracking using GPS How to handle privacy issues and concerns? Data Management Given the crucial role that data plays, it should not surprise you that data management is a core activity for any business, government agency, service organization, or charity. Data Management is a process that focuses on data collection, storage, and retrieval. Common data management functions include addition, deletion, modification, and listing. What is database? A shared, integrated computer structure that houses a collection of related data. A database contains two types of data: end-user data (raw facts) - raw facts, interest or preference of user metadata – data about data characteristics and relationship. Ex: metadata component Name = text Birthdate = date Age = number What is a database management system? The collection of programs that manages the database structure and controls access to the data stored in the database. A database resembles a very well-organized electronic filing cabinet in which powerful software (the DBMS) helps manage the cabinet’s contents. A database management system (or DBMS) is essentially nothing more than a computerized data-keeping system. A DBMS enables end users to create, protect, read, update and delete data in a database. It also manages security, data integrity and concurrency for databases. Role and Advantages of DBMS Role of DBMS The DBMS serves as the intermediary between the user and the database. The database structure itself is stored as a collection of files, and the only way to access the data in those files is through the DBMS. DBMS presents the end user (or application program) with a single, integrated view of the data in the database. Role of DBMS The DBMS receives all application requests and translates them into the complex operations required to fulfill those requests. The DBMS hides much of the database’s internal complexity from the application programs and users. The application program might be written by a programmer using a programming language, such as Visual Basic.NET, Java, or C#, or it might be created through a DBMS utility program. Advantages of DBMS Improved data sharing. The DBMS helps create an environment in which end users have better access to more and better-managed data. Improved data security. The more users access the data, the greater the risks of data security breaches. Corporations invest considerable amounts of time, effort, and money to ensure that corporate data is used properly. Better data integration. Wider access to well-managed data promotes an integrated view of the organization’s operations and a clearer view of the big picture. It becomes much easier to see how actions in one segment of the company affect other segments. Advantages of DBMS Minimized data inconsistency. Data inconsistency exists when different versions of the same data appear in different places. Improved data access. The DBMS makes it possible to produce quick answers to ad hoc queries. a query is a specific request issued to the DBMS for data manipulation. ad hoc query (user defined searches) is a spur-of-the-moment question. query result set collection of data rows returned by a query. data quality A comprehensive approach to ensuring the accuracy, validity, and timeliness of data. Improved decision making Increased end user productivity Types of Databases A single-user database supports A multiuser database supports only one user at a time. Ex: multiple users at the same time. Microsoft Access Types of Databases Workgroup database - Multiuser Enterprise database - The overall database that usually supports fewer company data representation, which than 50 users or is used for a specific provides support for present and department in an organization. expected future needs. Types of Databases A Centralized Database is a type of database A distributed database is basically a type of that is stored, located as well as maintained at database which consists of multiple databases a single location only. The centralized location that are connected with each other and are is accessed via an internet connection (LAN, spread across different physical locations. WAN, etc). Types of Databases Cloud database - A database that is created General purpose databases contain a wide and maintained using cloud services, such as variety of data used in multiple disciplines. Ex: Microsoft Azure or Amazon AWS. census Discipline-specific databases contain data focused on specific subject areas. The data in this type of database is used mainly for academic or research purposes. Ex: geographic information system (GIS) databases that store geospatial and other related data, Types of Databases Operational database - A database designed primarily to support a company’s day-to-day operations. Also known as a transactional database, OLTP database, or production database Analytical database - A database focused primarily on storing historical data and business metrics used for tactical or strategic decision making. Data warehouse - A specialized database that stores historical and aggregated data in a format optimized for decision support. Online analytical processing (OLAP) - A set of tools that provide advanced data analysis for retrieving, processing, and modeling data from the data warehouse. Types of Databases Business intelligence - A set of tools and processes used to capture, collect, integrate, store, and analyze data to support business decision making. Unstructured data (raw)- Data that exists in its original, raw state; that is, in the format in which it was collected. Structured data (formatted)- Data that has been formatted to facilitate storage, use, and information generation. Semistructured data - Data that has already been processed to some extent. Types of Databases Extensible Markup Language (XML) - is a special language used to represent and manipulate data elements in a textual format. An XML database supports the storage and management of semistructured XML data. Social media - Web and mobile technologies that enable “anywhere, anytime, always on” human interactions. NoSQL - A new generation of DBMS that is not based on the traditional relational database model. Database Design What is database design? It refers to the activities that focus on the design of the database structure that will be used to store and manage end-user data. Database Structure A database structure simply refers to how data is organized within a database. Here are the key components: Tables: The fundamental blocks of a database structure are the tables, which consist of rows and columns. Rows and columns: A crucial aspect of the database structure is the rows and columns. Rows show independent columns, whereas columns show attributes of those records. Poor database design Good database design Files System Data Processing Evolution of Files Systems Data Processing Manual File Systems - Typically, this was accomplished through a system of file folders and filing cabinets. Relatively small business reporting requirements. Computerized File Systems - computer-based system that would track data and produce required reports. Basic File Terminology Note: DP specialist had to create programs to retrieve the data from the file, manipulate it in whatever manner the user had requested, and present it as a printed report. SIMPLE FILE SYSTEM Problems with File Systems Data Processing Lengthy development times. The first and most glaring problem with the file system approach is that even the simplest data-retrieval task requires extensive programming. Difficulty of getting quick answers. The need to write programs to produce even the simplest reports makes ad hoc queries impossible. Complex system administration. System administration becomes more difficult as the number of files in the system expands. Lack of security and limited data sharing. Extensive programming. Making changes to an existing file structure can be difficult in a file system environment. Read records, transform original data, write the transformed data and repeat the steps for each record. Structural and Data Dependence A file system exhibits structural dependence - which means that access to a file is dependent on its structure. Logical Data Format – the way a person views data within the context of a problem Physical Data Format – the way a computer stores the data Structural independence - exists when you can change the file structure without affecting the application’s ability to access the data. Data Redundancy The organizational structure promotes the storage of the same basic data in different locations. Uncontrolled redundancy leads to: Poor data security Data inconsistency Data entry errors Data integrity problems Data Anomalies Data redundancy, however, fosters an abnormal condition by forcing field value changes in many different locations. Update anomalies Insertion anomalies Deletion anomalies Database Systems Database Systems The term database system refers to an organization of components that define and regulate the collection, storage, management, and use of data within a database environment. Database Components Hardware Software Application Programs People Procedures Data DBMS Functions Data dictionary management. The DBMS stores definitions of the data elements and their relationships (metadata) in a data dictionary. Data storage management. The DBMS creates and manages the complex structures required for data storage, thus relieving you from the difficult task of defining and programming the physical data characteristics. Data transformation and presentation. The DBMS transforms entered data to conform to required data structures. Security management. The DBMS creates a security system that enforces user security and data privacy. DBMS Functions Multiuser access control. To provide data integrity and data consistency, the DBMS uses sophisticated algorithms to ensure that multiple users can access the database concurrently without compromising its integrity. Backup and recovery management. The DBMS provides backup and data recovery to ensure data safety and integrity. Data integrity management. The DBMS promotes and enforces integrity rules, thus, minimizing data redundancy and maximizing data consistency. Database access languages and application programming interfaces. The DBMS provides data access through a query language. Database communication interfaces. A current-generation DBMS accepts end-user requests via multiple, different network environments. What are your take aways for today? References https://privacy.gov.ph/ https://www.researchgate.net/figure/The-Five-Principles-of-Informat ion-Management-The-framework-is-structured-in-three-steps_fig1_2 88708717 https://www.linkedin.com/pulse/information-management-skills-nira phai-jansawat