Managing data resources in a traditional file environment • An effective information system provides users with accurate, timely, and relevant information. • Accurate information is free of errors. • Information is timely when it is available to decision makers when it is needed. • Information is relevant when it is useful and appropriate for the types of work and decisions that require it. Database Approach to Data Management What is database? A database is a collection of related files containing records on people, places, or things. One of the most successful databases in modern history is the telephone book. For example: The telephone book is a collection of records on people and businesses who use telephones. The telephone book lists four pieces of information for each phone user: last name, first name, address, and phone number. Database Approach to Data Management Database Approach to Data Management • Organizing data in a relational database • A database organizes the data much the same way, grouping related pieces of data together. • The relational database is the most common type of database today. Relational databases organize data into two-dimensional table (called: relations) with columns and rows. Each table contains data on an entity and its attributes. For the most part, there is one table for each business entity. File Organization Terms and Concepts • File organization concepts • Computer system uses hierarchies • Field: Group of characters • Record: Group of related fields • File: Group of records of same type • Database: Group of related files • Record: Describes an entity • Entity: Person, place, thing on which we store information • Attribute: Each characteristic, or quality, describing entity • E.g., Attributes Date or Grade belong to entity COURSE File Organization Terms and Concepts • A computer system organizes data in a hierarchy that starts with the bit, which represents either 0 or 1. Bits can be grouped to form a byte to represent one character, number, or symbol. Bytes can be grouped to form a field, and related fields can be grouped to form a record. Related records can be collected to form a file, and related files can be organized into a database. Database Management Systems ▪ A database management system (DBMS) is software that permits an organization to centralize data, manage them efficiently, and provide access to the stored data by application programs. ▪ The DBMS is a specific type of software for creating, storing, organizing, and accessing data from a database. ▪ The DBMS acts as an interface between application programs and the physical data files. When the application program calls for a data item, such as gross pay, the DBMS finds this item in the database and presents it to the application program. Database Management Systems The DBMS relieves the programmer or end user from the task of understanding where and how the data are actually stored by separating the logical and physical views of the data. The logical view: it presents data as they would be perceived by end users or business specialists, whereas, The physical view: it shows how data are actually organized and structured on physical storage media. The database management software makes the physical database available for different logical views required by users. Database Management Systems Microsoft Access is a DBMS for desktop systems. MySQL is a popular open-source DBMS, and Oracle Database is a DBMS for small handheld computing devices. Database Management Systems Structured Query Language (SQL) Interactive Activity 1 True/False statements: 1. ( ) the DBMS enables the organization to centrally manage data, their use, and security. 2. ( ) Microsoft Access does not support creating a database. 3. ( ) database management systems enables generating reports and permitting a query. Problems with the Traditional File Environment ▪ In most organizations, systems tended to grow independently without a companywide plan. Accounting, finance, manufacturing, human resources, and sales and marketing all developed their own systems and data files. ▪ The traditional approach to information processing illustrates that each application, of course, required its own files and its own computer program to operate. For example: the human resources functional area might have a personnel master file, a payroll file, a medical insurance file, a pension file, a mailing list file, and so forth, until tens, perhaps hundreds, of files and programs existed. Problems with the Traditional File Environment From the Figure: What could illustrate?? Problems with the Traditional File Environment Five main problems with the traditional file environment are as: Data Redundancy and Inconsistency Data Dependence Lack of Flexibility Poor Security Lack of Data Sharing and Availability Problems with the Traditional File Environment Five main problems with the traditional file environment are as 1 - Data Redundancy and Inconsistency: Data redundancy is the presence of duplicate data in multiple data files so that the same data are stored in more than one place or location. Data redundancy occurs when different groups in an organization independently collect the same piece of data and store it independently of each other. Data redundancy wastes storage resources and also leads to data inconsistency. Data inconsistency is a situation where the same attribute may have different value. Problems with the Traditional File Environment Five main problems with the traditional file environment are as 2- Data Dependence: Data dependence refers to the coupling of data stored in files and the specific programs required to update and maintain those files such that changes in programs require changes to the data. In other shorten phrase, if changes in program requires changes to data accessed by program. 3- Lack of Flexibility: Lack of Flexibility where a traditional file system can deliver routine scheduled reports after extensive programming efforts, but it cannot deliver ad hoc reports or respond to unanticipated information requirements in a timely fashion. Problems with the Traditional File Environment Five main problems with the traditional file environment are as 4- Poor Security: It refers to that there is little control or management of data, access to and dissemination of information may be out of control. Management may have no way of knowing who is accessing or even making changes to the organization’s data. 5- Lack of Data Sharing and Availability: Because pieces of information in different files and different parts of the organization cannot be related to one another, it is virtually impossible for information to be shared or accessed in a timely manner. Capabilities of DBMS Relational vs Non-Relational Database Relational database It represents data as two-dimensional tables (called relations). For instance, a table with columns and rows, and even cells. Non-Relational databases It uses a more flexible data model and are designed for managing large data sets across many distributed machines and for easily scaling up or down. They are useful for accelerating simple queries against large volumes of structured and unstructured data (e.g., Web, Social media, graphics). Data Warehouse What is it and what does it do? A data warehouse is defined as “a database that stores current and historical data of potential interest to decision makers throughout the company where the data originate in many core operational transaction systems, such as systems for sales, customer accounts, and manufacturing, and may include data from Web site transactions”. – The data warehouse consolidates and standardizes information from different operational databases so that the information can be used across the enterprise for management analysis and decision making. How data warehouse works? The data warehouse extracts current and historical data from multiple operational systems inside the organization. These data are combined with data from external sources and reorganized into a central database designed for management reporting and analysis. The information directory provides users with information about the data available in the warehouse. Data warehouse outcomes ❖ The data warehouse makes the data available for anyone to access as needed, but it cannot be altered. ❖ A data warehouse system also provides a range of ad hoc and standardized query tools, analytical tools, and graphical reporting facilities Important Note: Many firms use intranet portals to make the data warehouse information widely available throughout the firm. Components of a data warehouse Peer Activity to answer the following question… Q: From the figure, name components of data warehouse. Data mining Definition The MIS literature is superabundant with "data mining" definitions. Three sufficient definitions are as follows: Data mining is an iterative process within which progress is defined by discovery, through either automatic or manual methods. It is a process of finding hidden patterns, relationship in datasets. It is the process and analysis of (often large) observational data sets to find unsuspected relationships and to summarize the data in novel ways that are both understandable and useful to the data owner. Data mining Examples customer buying patterns Infers rules to predict future behavior Data mining What is it and its types? Clustering Associations Sequences Forecasting Classification Data mining What is it and its types? Clustering It works in a manner similar to classification when no groups have yet been defined. In sequences , events are linked over time. Sequences Forecasting It uses predictions in a different way. It uses a series of existing values to forecast what other values will be. Data mining What is it and its types? Associations are occurrences linked to a single event. Associations Classification It recognizes patterns that describe the group to which an item belongs by examining existing items that have been classified and by inferring a set of rules. What is SQL? SQL (Structured Query Language) is the standard universal language used to communicate with Relational Database Management Systems (RDBMS). It is the primary tool for data analysts and backend developers to interact with enterprise systems directly at the source. Used to create and manage robust data architectures. Retrieves precise data points from millions of records in milliseconds. Updates and maintains data securely and efficiently, ensuring organizational data integrity. Why Use SQL in Business? Decision Support Handling Big Data Automated Reporting System Integration Providing accurate, Capability to process Creating fixed Seamlessly real-time data to millions of records queries to generate connecting management, much faster and daily, weekly, or operational eliminating more reliably than monthly reports databases to guesswork from traditional automatically, saving visualization tools strategic planning. spreadsheets. hundreds of hours. like Power BI or Tableau. The Foundation: Tables and Relations At the core of any Relational Database are Tables. Data is not stored in a chaotic pile, but in highly organized, spreadsheet-like structures. Table: The basic container for data. Example: A "Customers" table or a "Sales" table. Rows (Records): Horizontal entries representing individual instances. Columns (Fields): Vertical entries representing attributes. Relational Database A system that organizes data into multiple, separate tables to minimize redundancy, linked together through logical relationships. Data Integrity: Primary & Foreign Keys Keys are the invisible threads that hold a relational database together, ensuring data is accurate, accessible, and not duplicated. Primary Key (PK) Foreign Key (FK) A unique field that definitively identifies each A field in one table that refers to the Primary record in a single table. Key in another table, creating a structural Rule 1: It must be absolutely unique. Rule 2: It cannot be null (empty). Examples: , . relationship between the two. Purpose: Enforces referential integrity. Example: A the "Sales" table. field living inside Types of SQL Commands SQL is a broad language categorized by the specific actions the commands perform on the database. DQL DML DDL Data Query Language Data Manipulation Language Data Definition Language Used purely for fetching and Used for modifying the Used for defining and extracting data from the actual data living inside the modifying the structural database. tables. architecture. SELECT INSERT, CREATE, UPDATE ALTER Extracting Data: The SELECT Statement The SELECT statement is the most frequently used command in SQL. It reads and retrieves specific query.sql data from one or more tables without altering the underlying data. -- Retrieving specific columns SELECT column1, column2 FROM table_name; -- Business Example The Marketing team needs to launch an SMS campaign. They need a list of names and phone numbers extracted from the massive "Customers" database table. Business Use Case Execution SELECT FirstName, LastName, Phone FROM Customers; Precise Targeting: The WHERE Clause Retrieving all records from a table is rarely useful in business. The WHERE clause acts as a filter, extracting only the rows that fulfill a specific filter_query.sql condition. -- Using asterisk (*) selects ALL Business Example columns SELECT * FROM CommercialUnits A real estate investor is looking for premium WHERE SquareFootage > 5000 AND Status properties. The sales team uses SQL to list all = 'Available'; available commercial units where the square footage exceeds a certain threshold. Data Summarization & Statistics SQL is not just for extracting raw lists; it contains built-in Aggregate Functions to perform aggregate_query.sql mathematical operations on data sets. SUM(): Calculates total values. -- Example: Total sales revenue per branch SELECT BranchLocation, COUNT(): Counts the frequency of records. SUM(SalesAmount) AS TotalRev FROM AVG(): Calculates averages. SalesData GROUP BY BranchLocation ORDER BY TotalRev DESC; The GROUP BY clause groups rows that have the same values into summary rows (like a PivotTable). The Full Picture: Joining Tables Because relational databases split data into multiple tables to reduce redundancy, analysts must use JOIN commands to combine them back together for reporting. Function: Combines rows from two or more tables based on a related column between them (Primary/Foreign Keys). INNER JOIN: Returns records that have matching values in both tables. LEFT JOIN: Returns all records from the left table, and the matched records from the right table. Business Case: High-Value Customer Campaign Let's apply these SQL commands to solve a real-world business problem. 1. Scenario 2. Problem 3. Goal The Marketing Department They need a consolidated list of Extract a clean report containing wants to launch an exclusive customers whose total combined Customer Name, Phone promotion specifically targeting investments exceed $100,000. Number, and Total Spent using "High-Value Investors". SQL. Step 1: Analyzing the Schema Before writing code, we must understand the database structure (the schema). We identify that the data we need lives in two separate tables linked by a relationship. Table 1: Customers Columns: [CustomerID], [Name], [Phone] Table 2: Transactions Columns: [TransID], [CustomerID], [Amount] Step 2: Linking Data (INNER JOIN) We combine the customer identity (Name, Phone) with their financial transactions (Amount) using an INNER JOIN. We tell the database exactly how these tables relate by matching the Primary Key to the Foreign Key. SELECT Customers.Name, Transactions.Amount FROM Customers INNER JOIN Transactions ON Customers.ID = Transactions.CustID; Step 3: Aggregating and Filtering Finally, we group by the customer, sum their transactions, and use HAVING to filter aggregated totals > $100,000. SELECT Customers.Name, Customers.Phone, SUM(Trans.Amount) AS TotalSpent FROM Customers INNER JOIN Trans ON Customers.ID = Trans.CustID GROUP BY Customers.Name, Customers.Phone HAVING SUM(Trans.Amount) > 100000 ORDER BY TotalSpent DESC;
0
You can add this document to your study collection(s)
Sign in Available only to authorized usersYou can add this document to your saved list
Sign in Available only to authorized users(For complaints, use another form )