IM_Week2.pdf

COMP 112 – Information Management Prepared by: Glodelyn D. Ocfemia Objectives: Understand Understand the Information Management and data modeling Define Define data, information, metadata, database and database management system Determine Determine the concept of Database environme...

COMP 112 – Information Management Prepared by: Glodelyn D. Ocfemia Objectives: Understand Understand the Information Management and data modeling Define Define data, information, metadata, database and database management system Determine Determine the concept of Database environment Explain Explain the importance and components of DBMS  A method of using technology to collect, process and condense information with a goal of efficient management. This sometimes involves those who have a stake in or a right to that information. Management means the organization of and control over the structure, processing, and delivery of information.  1. Relevance – How do we find information relevant to our decisions? Key 2. Accessibility – How is the knowledge used to apply information captured and shared between employees? Challenges in 3. Legality – How organizations ensure they are using customer, employee and market information in Information accordance with legal and ethical standards? Management 4. Security – How do we protect this information from accidental or deliberate threats? 5. Value – How can this information help organizations reach their business objectives?  What is data modeling in Information Management? Data modeling is the process of creating a visual representation of either a whole information system or parts of it to communicate connections between data points and structures.  BASIC CONCEPTS AND DEFINITIONS Data * Data vs. Information * Metadata * Database Data Data vs. Information raw facts no context just numbers and Information text data with context processed data value-added to data – summarized – organized – analyzed 7  Metadata management is the administration of data that describes other data. It involves establishing policies and processes that ensure information can be integrated, accessed, shared, linked, analyzed and maintained to best effect across the organization. Metadata is data about data. In other words, it's information that's used to describe the data that's contained in something like a web page, document, or file. Another way to think of metadata is as a short explanation or summary of what the data is. Flat File Databases A flat-file database is a simple database that stores all data in a single table A flat-file database can be stored in a text file, such as a tab- delimited file; a spreadsheet; or in a database file that contains one or more unrelated tables. Database Concepts : Flat file example Record A single record will hold all the data relating to one unit of processing. e.g a track Field A field stores one item of data for the record File Data file contains a number of records Database Concepts : Data types (Access specific) - There are 5 main data types Text Characters Numeric Numbers Date Various formats Boolean True/False Counter Auto-inserted no.  Problems with flat files 1. Redundancy Large amounts of duplicated data Makes data entry slower Uses disk space Leads to other problems…  Problems with flat files 2. Reduced data integrity More likely to be inaccurate! Due to: – Data input errors – Inconsistent data entry  Problems with flat files 3. Difficult to update – If entries change all instances have to be updated 4. Security – All users have access to the same set of data 5. Program-Data Dependence – The user interface (amongst other things) is tied to a specific file. To create new views of data you would need to create new data files What is Database? A database is an organized collection of logically related data that is stored in a computer system. This is a collection of records stored in a computer in a systematic way, allows the users to enter, access, update and analyze their data quickly and easily. Examples of Databases Supermarket Credit card Travel Agent Library Insurance Hospital Bank University Student Database System enrollment RF payment DBMS of fees DB processing class official of grades cards receipt  Supermarket Database System inventory & tuna official cereal price check receipt sales update DB DBMS credit card check DBMS DB  The database environment A major requirement of any computer system is to store and retrieve data in a way that is meaningful to the end user – so the core of any Information System is data, which is to be transformed into information through data modelling. TRADITIONAL FILE PROCESSING SYSTEM Overview * Disadvantages of File Processing System  TRADITIONAL FILE PROCESSING SYSTEM It was totally computer based system where all the information is store in different computer files. stores data in a manner that all the departments of an organization have their own set of files that creates data redundancy.  Program-Data Dependence All programs maintain metadata for each file they use Data Redundancy Disadvantages Different programs have separate copies of the same data Limited Data Sharing of File No centralized control of data Processing Little opportunity to share data outside their own application. Excessive Program Maintenance System Creates a heavy program maintenance load in organization that rely on traditional file processing system Lengthy Development Times Programmers must design their own file formats Little opportunity to re-use previous development efforts THE DATABASE APPROACH Overview * Database Management System * Advantages of the Database Approach * Components of Database  Database Approach - Solution Requires a The database Database approach There is the Data is Management emphasizes the presence of System (DBMS) managed by integration and central that would sharing of data repository of controlling standardized and throughout the shared data. agent convenient store organization. and access database.  What is Database Management System? Is a software application that stores the structure of the database, the data itself, relationship among data in the database as well as forms and reports pertaining to the database. Is the software that interacts with end users, applications, and the database itself to capture and analyze the data. Provide a means of accessing that data stored inside the database.  Differences: DBMS vs. File System DBMS manages the resources like an operating system manages hardware resources  Components of the DBMS Environment Procedure People - log on - data admin Hardware Software Data - use of - database - DBMS - stored data software admin - PC - OS - meta-data - start/stop - mainframe - network - schema - backup - DB designer - network software - handle - application - application failures programmers programs - change - end users Bridge structure Machine Human Components of the DBMS Environment After the lesson expect that you will take your quiz in the Blackboard LMS