Dr. Chandra Amaravadi Western Illinois University INTRO TO ENTERPRISE DATABASES - II

IN THIS PRESENTATION.. Review of concepts from I Database Organization DBMS activities and functions Database approach Database application

Data vs Information Attribute, primary key File Record File processing DBMS activities, SQL, QBE Development cycle CONCEPTS INTRODUCED

Database – A group of related files File/table – A group of related records Record – a grouping of related fields Attr. value – value of an attr. e.g. hair color Attribute – property of an entity class Schema -- This is the logical view of the database (tables and fields) Primary key – An attribute whose values are unique within a file Secondary key – Any other attribute Database Files/tables Records Attr. values DATABASE ORGANIZATION

Primary key Record Attr. values Attributes/field names Structure/schema DATABASE ORGANIZATION PROD#DESCR.PRICEQUANTITY IR888ERefrigerator$1,80020 TS3233Television$6732 Record

THE DATA BASE APPROACH Enterprise Entity classes Data model (ER model) File 2 File 1 Data base cust. emp. Information!

THE DATABASE APPROACH.. Organizations need to collect and manage information. Typically this need can be summarized in terms of entity classes and their relationships Known as a data model/ER model ER model is converted to database model Implemented

THE BASIC CONCEPTS Entity – Individual example of person, place or thing. Entity Class – Collection of related entities. Attributes – Properties of entity classes about which we would like to collect information.

DISCUSSION John San Francisco (as a city) Customer Book Store# Xbox Microsoft Microsoft employees Invoice Production Classify the following as entity, entity class or attribute

AN EXAMPLE DATABASE APPLICATION

COMMON APPLICATIONS OF DATABASES Customers, products, vendors, orders Personnel, benefits Stock trades Financial transactions Orders search engines

THE STUDENT ADMINISTRATION APPLICATION ID and personal information Courses Registration Academic history Alumni The student administration application database consists of the following tables: What attributes are associated with each of these tables?

AN EXAMPLE APPLICATION.. registration transcripts process applns. admissions D.M. REGISTRAR ADMISSIONS COURSE SCHEDULING instructor/room assignment generate schedule avoid conflicts prospects mailings MARKETING Student Admin. database

Admissions enter information into database Printed in form of a report Checked if students meet requirements Student certificates validated Marked as accepted/rejected Student is cleared for registration System keeps track of registrations Checks clashes/ class limits Monitors enrollment Prints statistics THE STUDENT ADMINISTRATION APPLICATION

THE STUDENT ADMINISTRATION APPLICATION.. ID Table Id First/last/MI Student or faculty? Joins the U. Personal info. Table Id First/last/MI DOB Gender What DBMS Activity does this correspond to?

AN EXAMPLE APPLICATION.. Course Info. table Course# ? Registers id Course# Term Etc. Registration table

AN EXAMPLE APPLICATION.. Grade table ? Term Completes course

AN EXAMPLE APPLICATION.. Academic history id course# term term GPA cum GPA Grade Graduates id Year graduated degree major Alumni table

REPORTS AND QUERIES u List of students who graduated u List of students currently enrolled & their majors u List of students on hold u List of students who started in the current semester u List of students having GPA > 3.0

REPORTS AND QUERIES.. WESTERN ILLINOIS UNIVERSITY 10/12/2013 ACADEMIC STANDING REPORT FALL 2013 STUDENT ID LAST NAME FIRST NAME ADDR PHONE# CODE Roper Mark 12 Oak GS Pilani Maryann 4 Aggres PS GS -- Good standing PS -- Poor standing

SUMMARY OF DBMS ACTIVITIES  Define structure /schema  Enter data  modify data  query data  get reports Activities with DBMS

REVIEW QUESTIONS u Why are databases important? u What is the difference between a database and a DBMS? u Which is a bigger item, a file or a field? u What is data definition? u What are some common DBMS activities? u What is a data entry form used for? u What is SQL? QBE? u Do databases deal with data or information? u What is a file? u How do we get data out of the database? u Is a student an entity class or an attribute? u What is a synonym for an attribute?