CH. 11 Information and Data Management

Database Management Systems

1. A DATA DICTIONARY contains data about each file in the database and each field in those files. 2. A DBMS provides several tools that allow users and programs to retrieve and maintain data in the database: query language, query by example, form, and report writer. 3. A QUERY LANGUAGE consists of simple, English-like statements that allow users to specify the data to display, print, store, update, or delete. 4. STRUCTURED QUERY LANGUAGE (SQL) is a popular query language that allows users to manage, update and retrieve data. 5. Many DBMSs provide tools to guide nontechnical users through the steps of creating a query. 6. Most DBMSs include QUERY BY EXAMPLE (QBE), a feature that has a graphical user interface to assist users with retrieving data. 7. A FORM is a window on the screen that provides areas for entering or modifying data in a database. 8. A REPORT WRITER allows users to design a report on the screen, retrieve data into the report design, and then display or print the report. 9. A DBMS provides means to ensure that only authorized users access - access privileges and principle of least privilege policy. 10. A DBMS provides a variety of techniques to restore the database to a usable form in case it is damaged or destroyed: backup, log, recovery utility, and continuous backup.

Relational, Object-Oriented, and Multidimensional Databases

1. A DATA MODEL defines how users view the organization of the data. 2. A RELATIONAL DATABASE stores data in TABLES that consist of rows and columns: each ROW has a primary key and each COLUMN has a unique name. 3. A RELATIONSHIP is a link within the data. 4. An OBJECT-ORIENTED DATABASE (OODB) stores data in OBJECTS. Example of applications appropriate for an object-oriented database include: media database, groupware database, and CAD database. 5. A MULTIDIMENSIONAL DATABASE can store data in more than two dimensions of data - sometimes known as a hypercube; and can consolidate data much faster than a relational database. 6. A DATA WAREHOUSE is a huge database that stores and manages the data required to analyze historical and current transactions.

Information Systems in the Enterprise

1. An INFORMATION SYSTEM is a set of hardware, software, data, people, and procedures that work together to produce information. 2. ENTERPRISE RESOURCE PLANNING (ERP) integrates MRP II with the information flow across an organization to manage and coordinate the ongoing activities of the enterprise, including product planning, manufacturing and distribution, accounting and finance, sales, human resources, and customer support. 3. A DOCUMENT MANAGEMENT SYSTEM (DMS) allows for storage and management of a company's documents, such as word processing documents, presentations, and spreadsheets. 4. A CONTENT MANAGEMENT SYSTEM (CMS) enables and manages the publishing, modification, organization, and access of various forms of documents and other files, including media and webpages, on a network or the web. 5. A TRANSACTION PROCESSING SYSTEM (TPS) is an information system that captures and processes data from day-to-day business activities. 6. A MANAGEMENT INFORMATION SYSTEM (MIS) is an information system that generates accurate, timely, and organized information, so that managers and other users can make decisions, solve problems, supervise activities and track progress. 7. A DECISION SUPPORT SYSTEM (DSS) helps users analyze information and make decisions. 8. An EXPERT SYSTEM is an information system that captures and stores the knowledge of human experts and then imitates human reasoning and decision making.

Database Administration

1. DATABASE ANALYSTS and ADMINISTRATORS are responsible for managing and coordinating all database activities. 2. DATABASE ANALYST (DA) decides on proper placement of fields, defines data relationship, and identifies users' access privileges. 3. DATABASE ADMINISTRATOR (DBA) creates and maintains the data dictionary, manages security of the database, monitors the performance of the database, and checks backup and recovery procedures.

Databases, Data, and Information

1. DATABASE: collection of data organized in a manner that allows access, retrieval, and use of that data. 2. DATA: collection of unprocessed items (text, numbers, images, audio, and video). 3. INFORMATION: processed data (organized, meaningful, and useful). 4. DATABASE SOFTWARE, often called a DATABASE MANAGEMENT SYSTEM (DBMS), allows users to: create a computerized database; add, modify, and delete data; sort and retrieve data; and create forms and reports from the data. 5. DATA INTEGRITY reflects the quality of the data: the more errors the data contains, the lower its integrity; and data integrity is important because computers and people use information to make decisions and take actions. 6. Valuable information should have the following characteristics: accurate; verifiable; timely; organized; accessible; useful; and cost-effective. 7. Data is organized in layers - files, records, fields, characters. 8. A CHARACTER is one byte - numbers, letters, space, punctuation marks, or other symbols. 9. A FIELD is a combination of one or more related characters - field name, field size, and data type. 10. Common data types include: text, number, auto-number, currency, date, memo, yes/no, hyperlink, object, and attachment. 11. A RECORD is a group of related fields - a PRIMARY KEY is a field that uniquely identifies each record. 12. A DATA FILE is a collection of related records. 13. FILE MAINTENANCE refers to the procedures that keep data current: adding records, modifying records, and deleting records. 14. Users add new records to a file when they obtain new data. 15. Users generally modify a record to correct inaccurate data or update old data. 16. When a record is no longer needed, a user deletes it from a file. 17. VALIDATION compares data with a set of rules or values to find out if the data is correct: alphabetic/numeric check; range check; consistency check; completeness check; check digit; and other checks.

File Processing Versus Databases

1. FILE PROCESSING SYSTEM: each department has its own set of file; have data redundancy; and isolate data. 2. DATABASE APPROACH: programs and users share data; reduced data redundancy; improved data integrity; shared data; easier access; and reduced development time.

Web Databases

The web offers information about: jobs, travel, destinations, television programming, photos, movies, videos, local and national weather, sporting events, and legislative information.