Chapter 3 - Data Organization and Database Management System PDF

BIDGOLI MIS 6 3 DATABASE SYSTEMS, DATA WAREHOUSES, AND DATA...

BIDGOLI MIS 6 3 DATABASE SYSTEMS, DATA WAREHOUSES, AND DATA MARTS Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part.  LEARNING OUTCOMES 1 Define a database and a database management system 2 Explain logical database design and the relational database model 3 Define the components of a database management system 4 Summarize recent trends in database design and use 5 Explain the components and functions of a data warehouse MIS6 Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. | CH3 2  LEARNING OUTCOMES (continued) 6 Describe the functions of a data mart 7 Define business analytics, and describe its role in the decision-making process 8 Explain big data and its business applications Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 3  Databases Database Collection of related data that is stored in a central location or in multiple locations Data hierarchy: Structure and organization of data involving fields, records, and files Database management system (DBMS) Software for creating, storing, maintaining, and accessing database files Makes using databases more efficient Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 4 Exhib 3.2 Interaction Between the it User, DBMS and Database Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 5  Methods for Accessing Files Sequential access file structure Records are organized and processed in numerical or sequential order Organized based on a primary key Social Security numbers or account numbers Used for backup and archive files as they rarely need updating Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 6  Types of Data in a Database Internal Collected from within an organization Stored in the organization’s internal databases External Comes from a variety of resources Stored in a data warehouse Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 7  Methods for Accessing Files Random access file structure Records can be accessed in any order irrespective of the physical locations in storage media Fast and very effective when a small number of records need to be processed daily or weekly Records are stored on magnetic tapes Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 8  Methods for Accessing Files Indexed sequential access method (ISAM) Records are accessed sequentially or randomly depending on the number being accessed Random access is used for a small number Sequential access is used for a large number Uses an index structure and has two parts Indexed value Pointer to the disk location of the record matching the indexed value Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 9  Logical Database Design Physical view Involves how data is stored on and retrieved from storage media Hard disks, magnetic tapes, or CDs Logical view Involves how information appears to users and how it can be organized and retrieved Includes more than one logical view of data, depending on the user Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 10  Logical Database Design Data model Determines how data is created, represented, organized, and maintained Contains Data structure Operations Integrity rules Hierarchical model Relationships between records form a treelike structure Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 11 Exhib 3.3 A Hierarchical Model it Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 12  Logical Database Design Network model Similar to the hierarchical model but records are organized differently Includes multiple parent and child records Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 13 Exhib 3.4 A Network Model it Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 14  Relational Model Uses a two-dimensional table of rows and columns of data Rows are records Columns are fields Data dictionary: Stores definitions Data types for fields, default values, and validation rules for data in each field Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 15  Relational Model Primary key Uniquely identifies every record in a relational database Foreign key Field in a relational table that matches the primary key column of another table Used to cross-reference tables Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 16  Relational Model Normalization Improves database efficiency by eliminating redundant data Ensures that only related data is stored in a table Goes through different stages from first normal form (1NF) to fifth normal form (5NF) Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 17  Relational Model Retrieves data from tables using operations that pick and combine data from one or more tables Select Project Join Intersection Union Difference Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 18  Components of a DBMS Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 19  Database Engine Heart of DBMS software Responsible for data storage, manipulation, and retrieval Converts logical requests from users into their physical equivalents By interacting with other components of the DBMS Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 20  Data Definition Creates and maintains the data dictionary Defines the structure of files in a database Makes changes to a database’s structure Adding and deleting fields Changing field size and data type Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 21  Data Manipulation Used to add, delete, modify, and retrieve records from a database Uses a query language Structured Query Language (SQL) Standard fourth-generation query language that consists of several keywords specifying actions to take Query by example (QBE) Involves requesting data from a database by constructing a statement formed by query forms Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 22  Application Generation Designs elements of an application using a database Data entry screens Interactive menus Interfaces with other programming languages Used by IT professionals and database administrators Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 23  Data Administration Used for the tasks backup and recovery, security, and change management Used to determine who has permission to perform certain functions Summarized as create, read, update, and delete (CRUD) Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 24  Data Administration Database administrator (DBA) Handles database design and management Setting up database Establishing security measures to determine users’ access rights Developing recovery procedures when data is lost or corrupted Evaluating database performance Adding and fine-tuning database functions Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 25  Recent Trends in Database Design and Use Data-driven website Interface to a database Retrieves data and allows users to enter data Improves access to information Gives users more current information from a variety of data sources Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 26  Recent Trends in Database Design and Use Distributed database: Stores data on multiple servers throughout an organization Approaches to setting up a DDBMS Fragmentation: Addresses how tables are divided among multiple locations Replication: Each site stores a copy of the data in the organization’s database Allocation: Combines fragmentation and replication, with each site storing the data used most often Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 27  Recent Trends in Database Design and Use Object-oriented database: Single object contains data and their relationships Object consists of attributes and methods that can be performed on the object’s data Encapsulation: Grouping objects along with their attributes and methods into a single unit Inheritance: New objects can be created faster and easily by entering new data in attributes Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 28  Data Warehouses Collection of data from a variety of sources Used to support decision-making applications and generate business intelligence As they store multidimensional data, they are called hypercubes Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 29  Characteristics of Data in a Data Warehouse Characteristics of data in a data warehouse Subject oriented Comes from a variety of sources Categorized based on time Captures aggregated data Used for analytical purposes Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 30 Exhib 3.6 A Data Warehouse it Configuration Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 31  Input Different sources of data together provide input for a data warehouse to perform analyses and generate reports External data sources Databases Transaction files Enterprise resource planning (ERP) systems Customer relationship management (CRM) systems Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 32  Extraction, Transformation, and Loading (ETL) Processes used in a data warehouse Extracting data from outside sources Transforming data to fit operational needs Loading data into the database or data warehouse Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 33  Storage Collected information is organized in a data warehouse as: Raw data: Information in the original form Summary data: Gives users subtotals of various categories Metadata: Information about data’s content, quality, condition, origin, and other characteristics Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 34  Output Online transaction processing (OLTP) Facilitates and manages transaction-oriented applications Uses internal data and responds in real time Online analytical processing (OLAP) Generates business intelligence Uses multiple sources of information and provides multidimensional analysis Viewing data based on time, product, and location Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 35 Exhib 3.7 Slicing and Dicing Data it Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 36  Output Data-mining analysis: Discovers patterns and relationships Data warehouses help generate various types of information and reports for decision making Cross-reference segments of an organization’s operations for comparison purposes Generate complex queries and reports faster and easier Generate reports efficiently using data from a variety of sources Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 37  Output Find patterns and trends that can’t be found with databases Analyze large amounts of historical data quickly Assist management in making well-informed business decisions Manage high demand information from many users with different needs and decision making styles Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 38  Data Mart Smaller version of data warehouse, used by single department or function Advantages over data warehouses Access to data is faster due to their smaller size Response time for users is improved Easy to create because they are smaller and simple Less expensive Users are targeted better Has limited scope Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 39  Business Analytics (BA) Uses data and statistical methods to gain insight into the data Provides decision makers with information to act on Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 40  Types of BA Methods Descriptive analytics Reviews past events Analyzes the data Provides a report indicating what happened over a given period of time and how to prepare for future Reactive strategy Predictive analytics Prepares decision maker for future events Proactive strategy Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 41  Big Data Era Big data: Voluminous data which the conventional computing methods are unable to efficiently process and manage Involves dimensions known as 3 Vs Volume: Quantity of transactions Variety: Combination of structured and unstructured data Velocity: Speed with which data needs to be gathered and processed Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 42  Who Benefits from Big Data? Industries benefit and gain a competitive advantage in areas like: Retail Financial services Advertising and public relations Government Manufacturing Media and telecommunications Energy Healthcare Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 43  Factors in the Growth and Popularity of Big Data Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 44  KEY TERMS Allocation Big data Business analytics Create, read, update, and delete (CRUD) Data dictionary Data hierarchy Data mart Data model Data warehouse Database Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 45  KEY TERMS Database administrator (DBA) Database management system (DBMS) Data-driven website Data-mining analysis Distributed database management system (DDBMS) Encapsulation Extraction, transformation, and loading (ETL) Foreign key Fragmentation Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 46  KEY TERMS Hierarchical model Indexed sequential access method (ISAM) Inheritance Logical view Network model Normalization Object-oriented databases Online analytical processing (OLAP) Online transaction processing (OLTP) Physical view Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 47  KEY TERMS Primary key Query by example (QBE) Random access file structure Relational model Replication Sequential access file structure Structured Query Language (SQL) Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 48  SUMMARY In a database system, all files are integrated Retrieving data from a database is much faster Files are accessed by using a sequential, random, or indexed sequential method Components of a DBMS Database engine, data definition, data manipulation, application generation, and data administration Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 49  SUMMARY Recent trends in database design and use include data-driven websites, natural language processing, distributed and object-oriented databases Data marts focus on business functions for a specific user group in an organization Industries benefit from big data analytics and gain a competitive advantage Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 50 Copyright ©2016 Cengage Learning. All Rights Reserved. May not be scanned, copied or duplicated, or posted to a publicly accessible website, in whole or in part. MIS5 | CH3 51