Transcript chap05
Organizing Data and Information Chapter 5 Principles of Information Systems, Sixth Edition Principles and Learning Objectives • The database approach to data management provides significant advantages over the traditional file-based approach. – Define general data management concepts and terms, highlighting the advantages and disadvantages of the database approach to data management. – Name three database models and outline their basic features, advantages, and disadvantages. Principles of Information Systems, Sixth Edition Principles and Learning Objectives • A well-designed and well-managed database is an extremely valuable tool in supporting decision making. – Identify the common functions performed by all database management systems and identify three popular end-user database management systems. Principles of Information Systems, Sixth Edition Principles and Learning Objectives • The number and types of database applications will continue to evolve and yield real business benefits – Identify and briefly discuss current database applications. Principles of Information Systems, Sixth Edition The Hierarchy of Data Principles of Information Systems, Sixth Edition Data Entities, Attributes, and Keys Principles of Information Systems, Sixth Edition The Traditional versus the Database Approach to Data Management Principles of Information Systems, Sixth Edition The Traditional Approach Principles of Information Systems, Sixth Edition Traditional Approach • Data redundancy • Program-data dependence • Data integrity Principles of Information Systems, Sixth Edition Database Approach Principles of Information Systems, Sixth Edition Advantages of the Database Approach Principles of Information Systems, Sixth Edition Advantages of the Database Approach Principles of Information Systems, Sixth Edition Disadvantages of the Database Approach Principles of Information Systems, Sixth Edition Data Modeling & Database Models Principles of Information Systems, Sixth Edition Data Modeling and Database Models • Content - What data should be collected? • Access - What data should be given to what users? • Logical structure - How will the data be organized to make sense to a particular user? • Physical organization - Where will the data actually be located? Principles of Information Systems, Sixth Edition Data Modeling • Used to define and analyze data requirements needed to support the business processes of an organization. • Enterprise data modeling • Planned data redundancy • Data model • Entity-relationship diagrams Principles of Information Systems, Sixth Edition Enterprise Data Modeling • An Enterprise Data Model is an integrated view of the data produced and consumed across an entire organization. • An Enterprise Data Model (EDM) represents a single integrated definition of data, unbiased of any system or application. • It is independent of "how" the data is physically sourced, stored, processed or accessed. • The model unites, formalizes and represents the things important to an organization, as well as the rules governing them. Principles of Information Systems, Sixth Edition Entity-Relationship (ER) Diagrams Principles of Information Systems, Sixth Edition Data Models • Hierarchical models • Network models • Relational models Principles of Information Systems, Sixth Edition Hierarchical (Tree) Models Principles of Information Systems, Sixth Edition Network Models Principles of Information Systems, Sixth Edition Relational Models Principles of Information Systems, Sixth Edition Relational Models Principles of Information Systems, Sixth Edition Data Cleanup Principles of Information Systems, Sixth Edition Database Management Systems (DBMSs) • • • • • Provide a user view Create and modify the database Store and retrieve data Manipulate data Produce reports Principles of Information Systems, Sixth Edition Creating and Modifying the Database Principles of Information Systems, Sixth Edition Data Definition Language Principles of Information Systems, Sixth Edition Creating and Modifying the Database Principles of Information Systems, Sixth Edition Data Dictionary Benefits • • • • • • • • • • • • • A data dictionary is a reserved space within a database which is used to store information about the database itself. A data dictionary may contain information such as: Database design information Stored SQL procedures User permissions User statistics Database process information Database growth statistics Database performance statistics Reduced data redundancy. Faster program development. Easier data & information modification Increased data reliability. Principles of Information Systems, Sixth Edition Storing and Retrieving Data Principles of Information Systems, Sixth Edition Structured Query Language Principles of Information Systems, Sixth Edition Database Output Principles of Information Systems, Sixth Edition Popular Database Management Systems Principles of Information Systems, Sixth Edition Selecting a DBMS • • • • • • • Database size Number of concurrent users Performance Integration Features Vendor Cost Principles of Information Systems, Sixth Edition Database Management Systems Principles of Information Systems, Sixth Edition Data Warehouses Principles of Information Systems, Sixth Edition Comparison of OLTP and Data Warehousing Principles of Information Systems, Sixth Edition Distributed Databases Principles of Information Systems, Sixth Edition Open Database Connectivity (ODBC) Principles of Information Systems, Sixth Edition Summary • Data - one of the most valuable resources a firm possesses • Entity - a generalized class of objects for which data is collected, stored, and maintained • DBMS - a group of programs used as an interface between a database and application programs • Traditional on-line transaction processing (OLTP) do not support the types of data analysis needed today Principles of Information Systems, Sixth Edition