1 / 23

Chapter 5

0. Chapter 5. Database Concepts. Why Study Databases?. Databases have incredible value to business. Probably the most important technology for supporting operations. Vastly superior to file processing systems Businesses cannot survive without quality data about their

owen
Download Presentation

Chapter 5

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. 0 Chapter 5 Database Concepts

  2. Why Study Databases? • Databases have incredible value to business. • Probably the most important technology for supporting operations. • Vastly superior to file processing systems • Businesses cannot survive without quality data about their • internal operations and • external environment.

  3. Topics • Fundamental database structures. • Logical data elements. • Databases vs. Files Processing • Major types of databases. • Data warehouses and data mining.

  4. Data Resource Management Definition: • Managerial activity that applies information technology to the task of managing an organization’s data resources to meet the information needs of the stakeholders

  5. Foundation Data Concepts Abstract Concepts • Entity – person, place, object or event – stored as a record or a table row • Attribute – characteristic of an entity – stored as field or table column

  6. Foundation Data Concepts Database Concepts • Database – a collection of related tables • Tables – a collection of related records – collection of related entities • Record – collection of fields (table row) –represents an entity • Field – collection of characters (table column) – represents an attribute • Character – single alphabetic, numeric or other symbol

  7. Fields • Small to large • Characters “B R E I M E R” • Form a field • A field is an attribute of an entity

  8. Records • Small to large • A bunch of fields form a record • A record is an entity

  9. Tables • Small to large • A bunch of records forms a table • A table is a group of related entities

  10. 0 Databases • Small to large • A bunch of tables form a database • A database represents an organization or business

  11. 0 Databases • But, databases are not just a bunch of tables • A database also includes relationships between the different tables

  12. Traditional File Processing Definition: • Data is organized, stored, and processed in independent files of data records

  13. Problems of File Processing • Data Redundancy – duplicate data requires an update to be made to all files storing that data • Lack of Data Integration – data stored in separate files require special programs for output making ad hoc reporting difficult • Data Dependence – programs must include information about how the data is stored so a change in storage format requires a change in programs

  14. Database Management Approach Definition: • Consolidates data records into one database that can be accessed by many different application programs. • Software interface between users and databases • Data definition is stored once, separately from application programs

  15. Database Management Software (DBMS) Definition: • Software that controls the creation, maintenance, and use of databases

  16. DBMS Software Components • Database Definition • Language and graphical tools to define entities, relationships, integrity constraints, and authorization rights • Application Development • Graphical tools to develop menus, data entry forms, and reports

  17. DBMS Software Components • Transaction Processing • Controls to prevent interference from simultaneous users and • Controls to recover lost data after a failure • Database Tuning • Tools to monitor and improve database performance

  18. Database Interrogation Definition: • Capability of a DBMS to report information from the database in response to end users’ requests • Query Language – allows easy, immediate access to ad hoc data requests • Report Generator - allows quick, easy specification of a report format for information users have requested

  19. Natural Language vs. SQL Queries

  20. Database Maintenance • Updating a database continually to reflect new business transactions and other events • Updating a database to correct data and ensure accuracy of the data

  21. Application Development • End users, systems analysts, and other application developers can use the internal programming language and built-in software development tools provided by many DBMS packages to develop custom application programs.

More Related