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

IN THIS PRESENTATION.. Basic concepts: data and info, entity, attr, pkey, file, record Need for databases Historical approach to data Definitions Database organization DBMS and DBMS activities and functions Importance of databases/Organizational importance Course features

WHAT IS INFORMATION?

DEFINING DATA AND INFORMATION Data: Data consists of raw facts e.g. 2982034 USA 30 32 31 93 Great Britain 19 20 12 51 China 19 15 20 54 Germany 13 8 9 30 Russia 12 14 15 41 Japan 10 5 18 33 France 8 11 12 31

DATA VS INFORMATION Country Gold Silver Bronze Total USA 30 32 31 93 Great Britain 19 20 12 51 China 15 54 Germany 13 08 09 Russia 14 41 Japan 10 5 18 33 France 11 Italy 06 23 Data becomes information when we ________________ it.

NEED FOR DATABASES We live in an information age cannot function without information can be a life or death issue finding acct balance print transaction history order spare parts for MRI machine find patient records needs to be a click away otherwise, lost sale, lost profits or lost career! How can we find information when we need it?

BASIC ORGANIZATION CONCEPTS (Entity, attribute, primary key, file, record)

INTRODUCING ENTITIES, ECLASSES AND ATTRIBUTES Information is a collection of facts usually DESCRIBING something. What does it describe here? How? Name: Steve Nash DOB: 2-7-1980 Profession: Basket ball player Address: 415 Walnut street.

COLLECTION OF DATA... Following is another example of information as a collection of facts describing a transaction. Acct#: 4555950 Date: 12/5/16 Time: 4:48 pm Merchant: WIU Union Card type: Master Card Issuer: First Bank ______describe a transaction more.

ONE ATTRIBUTE HAS A UNIQUE VALUE One of these attributes always has a unique value which one is it? Acct#: 4555950 Date: 12/5/16 Time: 4:48 pm Merchant: WIU Union Card type: Master Card Issuer: First Bank The unique attribute is Called a ______________

ORGANIZATION CONCEPTS What can we say about these two sets of data? Transaction#: 55643 Date: 12/5/16 Time: 4:09 pm Merchant: WIU Union Card type: Master Card Issuer: First Bank Transaction#: 55644 Date: 12/5/16 Time: 4:20 pm Merchant: Vitales Card type: Master Card Issuer: Midwest Bank ____________________________

ORGANIZATION CONCEPTS.. Transaction#: 55643 Date: 12/5/16 Time: 4:09 pm Merchant: WIU Union Card type: Master Card Issuer: First Bank ________ Transaction ID Date Time Merchant 55643 12/05/16 4:09 pm WIU Union 55644 4:20 pm Vitales Data can be organized into a _____ with ________

DEFINITION OF A FILE.. A database ______ is a collection of _______ . CBT QUALITY MANAGEMENT COMMITTEE Meeting Minutes Meeting Date/time: December 2nd, 2:00 p.m. Present: Brad Burke, Ken Dien, Chin Yi, John Smith 1215 Oak Drive $515.00 11/5/16 Mary Ash 415 Ponds $ 56.00 5/9/16 A database ______ is a collection of _______ .

DATABASE

DATABASE Database - A shared collection of logically related data designed to meet the needs of multiple users in an organization. Example, cars listed in auto-trader Matches played in the olympics Properties owned by a company Books available from Amazon.com DBMS is the software program.

DATABASE ORGANIZATION Structure/schema Attributes/field names Primary key PROD# DESCR. PRICE QUANTITY IR888E Refrigerator $1,800 20 TS3233 Television $67 32 Record Record A database has a structure or schema that organizes the data into attributes. Collections of attribute values become records. A primary key guarantees unique access. Attr. values

DATABASE ORGANIZATION 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 Schema -- This is the structure or logical view of the database (tables and attr.) Primary key – An attribute whose values are unique within a file Secondary key – Any other attribute Database Files/tables Records Attr. values

HISTORICAL APPROACH TO DATA The historical method of handling data is called file processing 55643 3/02/16 4:09pm WIU Union 55644 5/08/16 4:20pm Vitales 55644 7/05/16 4:20pm Vitales 55646 12/11/16 8:05am Pizza Hut 55643 $25.60 MC WIU Union 55644 $38.00 Visa Vitales 55644 $63.00 Visa Vitales 55646 $55.00 Amex Pizza Hut File 1 File 2 Instead of storing data centrally in a database, in the file processing approach, the same data was often duplicated in multiple files.

FILE PROCESSING PROBLEMS What problems did the file processing approach result in?

DATABASE MANAGEMENT SYSTEMS (DBMS)

DBMS DBMS - software program to create, manage and provide controlled access to the data Example Access, Oracle, DB2 What can we do with a DBMS?

DBMS ACTIVITIES & FUNCTIONS The operations that can be carried out with a DBMS include: Define structure / schema Enter data modify data query data get reports

DBMS ACTIVITIES & FUNCTIONS Define structure/schema Field Name Data type Description Length Decimals Prod# Numeric Unique prod code 6 Descr Text Short prod description 25 Price Currency Product price 2 This is called data definition

DATA ENTRY EMPLOYEE DATA ENTRY EMP ID: NAME: Title Label Field A data entry form allows data to be entered easily. Title EMPLOYEE DATA ENTRY Label EMP ID: Field NAME: Data entry form

ENTERING DATA EMPLOYEE DATA ENTRY EMP ID: NAME: 1117 John The data is entered into the data entry form This is called data entry. Where does the data go to?

RETRIEVING DATA Data can be obtained from the database in the following ways: By the user SQL commands QBE (Query by Example) Reports Via an application program SQL commands only

RETRIEVING DATA THE STRUCTURED QUERY LANGUAGE Each SQL statement has three parts as shown below: SELECT is used to select attributes needed FROM is used to specify the tables from which data is obtained. WHERE is used for including criteria (filter) Select car_id, car_color, car_price, car_mileage From cars Where car_mileage < 100,000

RETRIEVING DATA.. Write an SQL statement for listing names of employees in finance department. Employee Emp ID Emp Name Department Join Date 1115 John Finance 4/9/16 1117 Han Sales & Mktg. 12/16/16 1120 Mary Human Resources 1/19/16 SELECT ?? FROM ?? WHERE ?? This is called query/retrieval.

QUERY BY EXAMPLE List names of employees in finance department. Emp ID Emp Name Department Join Date “finance” A query by example form (QBE) This is also another form of query/retrieval.

RETRIEVING DATA: REPORTS.. We can get data out through queries or reports Reporting resembles COBOL reports Report specification needs to be created Consists of RH, PH, Detail, RF, PF Report is generated from specification

SPECIFYING REPORTS.. A report specification RH Title PH Column PRODUCT LISTING Title PH Column Headings PRODUCT # DESCR. PRICE Detail Product # Descr. Price Fields PF Average Price Footer RF A report specification

SUMMARY OF DBMS ACTIVITIES Activities with DBMS define structure/schema enter data (into table/tables) modify data (not discussed) query data (from table/tables) get reports (from table/tables)

USAGE OF DATABASES Databases are used (operational): To store and record information e.g. bal, price, grades etc. To retrieve information e.g. check#432 cashed? To report information e.g. daily sales To answer queries e.g. how many shoes were sold? Advanced uses (Strategic): To analyze trends Identify sales prospects

OPERATIONAL & STRATEGIC USAGE What if a customer wants to return a tie purchased in a store? What if a manager wants to know what products were sold on a particular day? Suppose we have detailed information on each and every transaction in a store, what can we do with that?

THE DEVELOPMENT CYCLE

THE DATABASE DEVELOPMENT CYCLE How do we know what information we need for the database?

THE DATABASE DEVELOPMENT CYCLE.. The database development cycle parallels the information systems development cycle. database planning database analysis database design implementation support/maintenance

THE DATABASE DEVELOPMENT CYCLE.. Planning It is concerned with identifying what information will be in the database and the resources that will be required. Analysis This is concerned with the detailed requirements such as attributes, entity classes as well as with their relationships. Design It is concerned with creating a database structure that will fulfill the requirements Implementation This is the phase that is concerned with actually defining the structures, entering data and creating reports. Maintenance This is concerned with ensuring that the schema, reports etc are up to date and the database is performing well.

THE DEVELOPMENT CYCLE AND THIS COURSE.. Database environment -- Evolution & environment Database planning -- Enterprise analysis Analysis -- Database analysis Design -- Logical design Design -- Physical design Implementation -- Access, MySQL assignments Support/maintenance -- Database adminstration.

ABOUT THE COURSE

COURSE OBJECTIVES Thorough understanding of database concepts Ability to develop ER models Ability to develop database designs Ability to implement databases in PC based systems Ability to write SQL queries Familiarity with database administration issues Ability to analyze database requirements and implement systems for a small organization

COURSE FEATURES Very concept oriented Database concepts are abstract Participation required! Digressions welcome! Guidelines are very subjective Numerous in-class exercises Reinforcing assignments Need to have a good “schema”!

COURSE EVALUATION EVALUATION ITEM POINTS Six assignments* 100 Midterms 200 Final Quizzes (2 x 20) 40 Participation Attendance 20 Total 500 *Lowest will be dropped, but -20 point penalty for non-submission Note: Please refer to your course syllabus for up to date information on the evaluation schedule.

CLASS PARTICIPATION Answer questions Raise an issue relevant to the topic at hand Solve an in-class problem Participation quizzes Max, two “tallies” per session Quality and quantity of participation Disruptive activities negatively assessed Review powerpoints before coming to class!

GENERAL COMMENTS Database practice is an application of theory Get theories/frameworks and definitions into your system; Need to have good conceptual understanding Need to review frequently (before class, after class and everyday) Participate in class Exams cover all topics (don’t strategize) Most important course in the IS curriculum