tailieunhanh - Lecture Introduction to Computers: Chapter 11A - Peter Norton's
Chapter 11A - Database management systems. This chapter define the terms database and database management system (DBMS), list at least three tasks that a DBMS enables users to do, differentiate between flat-file databases and relational databases, list three steps needed to create a database, explain the purpose of filters and forms, list three examples of query languages. | McGraw-Hill Technology Education Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 11A Database Management Systems Database Management Systems Database management system (DBMS) Store large collections of data Organize the data Becomes a data storage system 11A- Discussion point Ask your student if anyone knows why sorting by zip code is important. Hopefully, someone knows that the post office provides a discount on presorted mail. The Database Stores a collection of related items Collection is arranged in a structure Organizes and describes the data Often includes helper documents Two different types 11A- Teaching tip Figure on page 423 describes the database structure Database Structure Field Name Record Field 11A- The Database Fields Hold an individual piece of data Are named descriptively Often called a column Phone book examples Name, address, e-mail, phone number Fields may contain no data 11A- The Database Records One full set of fields Often called a row Phone book example Smith, Joe, 123 Some Street, 412-555-7777 Databases may have unlimited rows 11A- The Database Tables One complete collection of records Databases may have thousands of tables 11A- Database Helper Documents Forms Present one record to the user Often used to change or view data 11A- Teaching tip Figure on page 423 provides examples of forms and reports. Database Helper Documents Reports Produce printed results from the database Includes tools to summarize data 11A- Flat-file Databases Typically has only one table If multiple, each has a separate file Useful for simple data storage needs Hard to manage large data needs Can waste disk space 11A- Teaching tip Start your students thinking about real databases, with millions of records. Using PA instead of Pennsylvania saves 10 bytes per record. In a database with 1 million records, this saves 10,000,000 bytes. This is roughly equal to a stack of 10 floppy disks . | McGraw-Hill Technology Education Copyright © 2006 by The McGraw-Hill Companies, Inc. All rights reserved. Chapter 11A Database Management Systems Database Management Systems Database management system (DBMS) Store large collections of data Organize the data Becomes a data storage system 11A- Discussion point Ask your student if anyone knows why sorting by zip code is important. Hopefully, someone knows that the post office provides a discount on presorted mail. The Database Stores a collection of related items Collection is arranged in a structure Organizes and describes the data Often includes helper documents Two different types 11A- Teaching tip Figure on page 423 describes the database structure Database Structure Field Name Record Field 11A- The Database Fields Hold an individual piece of data Are named descriptively Often called a column Phone book examples Name, address, e-mail, phone number Fields may contain no data 11A- The Database Records One full set
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