![Example (cont.)
The SQL Statement to perform the query:
SELECT INSTRUCTOR.academicTitle, INSTRUCTOR.instructorName,
INSTRUCTOR.lastName, DEPARTMENT.departmentName
FROM DEPARTMENT INNER JOIN INSTRUCTOR ON
DEPARTMENT.[departmentID] = INSTRUCTOR.[departmentID]
WHERE DEPARTMENT.departmentName = ‘Economics’;
11/17/2016 MGIS 301 Management Information Systems
Thank God, I
don’t have to
know this in
MGIS 301!
26](https://image.slidesharecdn.com/mgis301databasetechnologies-161117045956/85/MGIS-301-Databases-and-Database-Technologies-26-320.jpg)
MGIS 301 Databases and Database Technologies
- 1. MGIS 301 Management Information Systems Week 04 Databases and Database Technologies M. Murat Albayrakoglu
- 2. Agenda • Transferable skill • Database concepts • Database design • Database management system (DBMS) 11/17/2016 MGIS 301 Management Information Systems 2
- 3. Transferable Skills • Any skill that applies to various roles and tasks throughout an individual’s career • Can be acquired via various activities • Informal • Formal • Categories • Communication skills • Analytical skills • Technical skills • Personal skills • Organizational skills Database skills = Knowledge + Practice 11/17/2016 MGIS 301 Management Information Systems 3
- 4. Database Concepts 11/17/2016 MGIS 301 Management Information Systems 4
- 5. Basics • Bit (b): 0 or 1 • Byte (B): 8 bits; size of each ASCII character • Data storage needs measured in kB = 103 B MB= 106 B GB = 109 B TB = 1012 B PB = 1015 B EB = 1018 B ZB = 1021 B 11/17/2016 MGIS 301 Management Information Systems 5
- 6. Database Definition • A database is an organized collection of related data • A database has a purpose has users has structure describes a relevant part of the real world 11/17/2016 MGIS 301 Management Information Systems 6
- 7. Database Advantages • Program-data independence • Data changes without changing programs • New programs can use existing data • Planned data redundancy • Limited replication of data • Storage space efficiency • Improved data consistency • Reduced chance for data inconsistency • Improved data sharing • Authorized users • User view specific to a task • Increased productivity of application development • Focus on accessing data rather than creating and updating data • Focus on functionality 11/17/2016 MGIS 301 Management Information Systems 7
- 8. Database Advantages (cont.) • Enforcement of standards • Single authority to enforce data standards: DBA • Improved data quality • Entry and modification constraints • Integrity constraints • Improved data accessibility and responsiveness • Easy to get data from within the authorized user views • Reduced program maintenance • No impact of data changes on the programs to a certain limit • Improved decision support • Fast access to high quality data • Faster and more accurate decisions 11/17/2016 MGIS 301 Management Information Systems 8
- 9. Database Disadvantages • New IT specialists • Database developers and administrators • Installation and maintenance costs • Getting, operating and maintaining multi-user systems • Apparent complexity • User, developer and administrator training • Conversion costs • Changing from legacy systems to a database environment • Security and continuity risks • Backup and recovery issues • Organizational conflicts • Data definition, ownership, and maintenance rights 11/17/2016 MGIS 301 Management Information Systems 9
- 10. Database Models Pre-Relational and Relational Models • Flat file model • Hierarchical database model • Network database model • Relational database model (in this course) • Object-relational database model Post-Relational Models (after Web 2.0) • Object database model • Column-based database model • Key-value database model • Document-based database model • Graph database model • Hybrid database models 11/17/2016 MGIS 301 Management Information Systems 10
- 11. Relational Database Model History • Edgar F. Codd proposed the model in 1970 • Based on the concepts of relational algebra • First commercial implementation in 1979 • Oracle’s SQL RDBMS Major players today • Proprietary • IBM DB2 • Microsoft Access • Microsoft SQL Server • Oracle • Open source • MySQL • PostGRE SQL • SQLite 11/17/2016 MGIS 301 Management Information Systems 11
- 12. Relations • Relation (Table) • Named and two-dimensional table, e.g. INSTRUCTOR • Contains columns e.g. instructorID, instructorName, lastName, academicTitle, dateEmployed • Contains data, e.g. 555551, Mehmet Murat, Albayrakoglu, Instructor, 15/09/2016 in its rows • Attribute (Field) • Each named column of a relation, e.g. instructorName, lastName, academicTitle • Of a particular data type, e.g. text, integer, decimal, date, hyperlink, Boolean, date etc. • Tuple (Record) • Each unnamed row of a relation • Made up of data cells 11/17/2016 MGIS 301 Management Information Systems 12
- 13. Example: A Table 11/17/2016 MGIS 301 Management Information Systems 13
- 14. Keys • Primary key • An attribute (or combination of attributes) whose value is unique across all occurrences of a relation • e.g. studentID, citizenshipNo, productID. • Composite key • An attribute that has meaningful components • e.g. studentID = 20150112007 is made up of admissionYear = 2015 collegeID = 01 departmentID = 12 registrationNo = 007 • Foreign key • An a nonprimary attribute in one relation that appears as a primary key in another • e.g. departmentID in INSTRUCTOR relation. 11/17/2016 MGIS 301 Management Information Systems 14
- 15. Keys: Examples • Primary key INSTRUCTOR(instructorID, instructorName, lastName, academicTitle, dateEmployed) COURSE(courseID, courseName, creditHRS) DEPARTMENT(departmentID, departmentName) • Composite key INSTRUCTORCOURSE(instructorID, courseID, courseCoordinator) • Foreign key INSTRUCTOR(instructorID, instructorName, lastName, academicTitle, dateEmployed, departmentID) INSTRUCTORCOURSE(instructorID, courseID, courseCoordinator) 11/17/2016 MGIS 301 Management Information Systems 15
- 16. 11/17/2016 MGIS 301 Management Information Systems Primary Keys 16
- 17. 11/17/2016 MGIS 301 Management Information Systems Composite Key 17
- 18. Foreign Key 11/17/2016 MGIS 301 Management Information Systems 18
- 19. 11/17/2016 MGIS 301 Management Information Systems Foreign Keys 19
- 20. Relational Algebra • An algebra is a mathematical system of operands and operators • Operands • Relations (tables) • Operators • Union • Intersection • Difference • Selection • Projection • Join • Renaming Used for creating a programming language, known as SQL, capable of creating and modifying relations and relationships, as well as, manipulating data contained in one or more relations 11/17/2016 MGIS 301 Management Information Systems 20
- 21. Tuple (Record) Operations: CRUD • In a given relation • Create • Creates a new tuple • Read • Reads an existing tuple • Update • Updates an existing tuple • Delete • Deletes an existing tuple 11/17/2016 MGIS 301 Management Information Systems 21
- 22. Data Entry • Electronic forms (e-forms) • Mostly browser based • Form elements • Label • Text box • Radio button • Check box • Menu • Slider • Action buttons (Save, Submit, OK, Cancel, Help etc.) • etc. 11/17/2016 MGIS 301 Management Information Systems 22
- 23. Example: A Raw Form 11/17/2016 MGIS 301 Management Information Systems 23
- 24. Queries • Filtered data for a specific purpose • To make a query • Decide what data are required • Define a criterion to select data to fulfill the requirement • Identify the relations and the fields that holds the data • Perform the query • To perform a query • Write an SQL statement • Use a query-by-example (QBE) tool 11/17/2016 MGIS 301 Management Information Systems 24
- 25. Example: A Query 11/17/2016 MGIS 301 Management Information Systems 25
- 26. Example (cont.) The SQL Statement to perform the query: SELECT INSTRUCTOR.academicTitle, INSTRUCTOR.instructorName, INSTRUCTOR.lastName, DEPARTMENT.departmentName FROM DEPARTMENT INNER JOIN INSTRUCTOR ON DEPARTMENT.[departmentID] = INSTRUCTOR.[departmentID] WHERE DEPARTMENT.departmentName = ‘Economics’; 11/17/2016 MGIS 301 Management Information Systems Thank God, I don’t have to know this in MGIS 301! 26
- 27. Reports • A report is an organized and summarized data for a particular purpose • Report elements • Tables • Charts • Report types • Regular reports • Time-triggered reports • Event-triggered reports • Ad-hoc reports • On a per-requirement basis 11/17/2016 MGIS 301 Management Information Systems 27
- 28. 11/17/2016 MGIS 301 Management Information Systems Example: A Raw Report 28
- 29. Database Design 11/17/2016 MGIS 301 Management Information Systems 29
- 30. Database Design • Modeling organizational data • Output: Conceptual data model • A representation of the organizational data (ERD) • Conceptual database design • Output: Conceptual database model • A representation of normalized data in detail • Physical database design • Output: Physical database model • Specific DBMS representation the conceptual database model • Next: Database implementation (in the labs) • Programming the database visually or with SQL programming language 11/17/2016 MGIS 301 Management Information Systems 30
- 31. Steps of Conceptual Database Design 1. Determine the relevant entities 2. Indicate the relevant attributes of each entity type 3. For each entity, decide which one(s) of these characteristics can be a candidate for uniquely identifying the entity 4. Set the most useful candidate key as the identifier 5. Determine the relationships among the entities 6. Connect entities through relationships 7. Determine the business rules 8. Indicate the cardinality of the relationships 11/17/2016 MGIS 301 Management Information Systems 31
- 32. Entities • Similar persons, places, things, events, or concepts • Categories of data • The symbol and an example ENTITY attribute1 attribute2 … attributeM STUDENT studentID nationalID studentName lastName birthDate birthPlace gender cellPhone eMail homeAddress yearAdmitted yearIn cumGPA yearGraduated Candidate keys Entity name (singular) Attribute list Identifier 11/17/2016 MGIS 301 Management Information Systems 32
- 33. Entities (cont.) • Entity type • Similar entities • Three generic entity types • Strong entity • Weak entity • Associative entity • Entity instance (or occurrence) • Single example of an entity 11/17/2016 MGIS 301 Management Information Systems 33
- 34. Entities and Entity Instances STUDENT studentID nationalID studentName lastName birthDate birthPlace gender cellPhone eMail homeAddress yearAdmitted yearIn cumGPA yearGraduated STUDENT 0000001 555 55 555 551 Emin Kendinden Jul. 20, 1999 Ankara Male +905555555551 eken@ku.edu.tr … … … … … Entity Entity instance11/17/2016 MGIS 301 Management Information Systems 34
- 35. Attributes • Attributes • Relevant characteristics of each entity for the organization • Each attribute belongs to a domain, e.g. text, integer, date, hyperlink, file etc. • Candidate key • One or more of the attributes of a particular entity that is used to identify each specific occurrence of the entity • e.g. the citizenship number, tax ID, or school ID. • Identifier • The candidate key chosen to be the unique identifying characteristic of each entity 11/17/2016 MGIS 301 Management Information Systems 35
- 36. Attribute Types • Multivalued attribute, e.g. phone numbers • Repeating group, e.g. children or various addresses • Required attribute, e.g. student ID • Optional attribute, e.g. second name • Composite attribute, e.g. course ID and student ID • Derived attribute, e.g. age = today – birthDate 11/17/2016 MGIS 301 Management Information Systems 36
- 37. Relationships • Any association of two or more instances of entities relevant to a business • Degrees of a relationship • Unary (advanced) • Binary (in this course) • Ternary (advanced) • Normalized relationships • Necessary to preserve data integrity 11/17/2016 MGIS 301 Management Information Systems 37
- 38. Relationships: Depiction • Entity 1 does something to Entity 2 • Something is done to Entity 2 by Entity 1 ENTITY 2 attribute1 attribute2 … attributeN ENTITY 1 attribute1 attribute2 … attributeM Something_done_by Does_something_to 11/17/2016 MGIS 301 Management Information Systems 38
- 39. Relationships: Example COURSE courseID courseName creditHrs … STUDENT studentID studentName lastName … Taken by Takes 11/17/2016 MGIS 301 Management Information Systems 39
- 40. Relationships: Optionality and Cardinality Cardinality One Many Optionality Optional Optional one Optional many Mandatory Mandatory one Mandatory many • Optional one • Mandatory one • Optional many • Mandatory many • Minimum and maximum cardinalities may be defined • e.g. a class section may have between a minimum of 5 and a maximum of 50 students 11/17/2016 MGIS 301 Management Information Systems 40
- 41. Optionality and Cardinality Example • From left-to-right: A student always takes one or more courses • From right-to-left: A course is sometimes taken by one or more students COURSE CourseID courseName creditHrs … STUDENT studentID studentName lastName … Taken by Takes 11/17/2016 MGIS 301 Management Information Systems 41
- 42. Cardinality Types 11/17/2016 MGIS 301 Management Information Systems 42 One-to-one One-to-many Many-to-many
- 43. More Examples and Exercises Consider the following relationships. Describe the two-way relationships in plain English. Draw the ERD segments connecting each pair. • INSTRUCTOR advises STUDENT • STUDENT gets PC • STUDENT earns SCHOLARSHIP • STUDENT lives in ROOM • ROOM contains FURNITURE • ROOM belongs to DORM • PUBLISHER publishes BOOK • AUTHOR writes BOOK • BOOKSTORE sells BOOK • BOOKSTORE ships BOOK • CUSTOMER orders BOOK • CUSTOMER pays for BOOK 11/17/2016 MGIS 301 Management Information Systems 43
- 44. Degree of Relationships • Number of entities participating in a relationship Unary Binary Ternary 11/17/2016 MGIS 301 Management Information Systems 44
- 45. Entity Relationship Diagram (ERD) • Create entity-relationship segments • Combine them to a complete diagram E1 E2 E2 E3 E1 E4 E1 E2 E3 E4 11/17/2016 MGIS 301 Management Information Systems 45
- 46. Conceptual Database Design 1. Normalize the relationships in the data model (ERD) 2. Transform entities into relations 3. Create relationships 4. Merge relations 11/17/2016 MGIS 301 Management Information Systems 46
- 47. Normalization • Normalization is a process for converting a single many-to-many relationship into two one-to-many relationships • Normalization helps • Avoid data anomalies • Protect data integrity COURSE CourseID courseName creditHrs STUDENT studentID studentName lastName … Takes STUDENTCOURSE studentID CourseID GradeTaken by Refers to Referred by 11/17/2016 MGIS 301 Management Information Systems 47
- 48. Transforming Entities into Relations • A relation has the following form: • ENTITY(primaryKey, attribute1, attribute2, … , attributeN) • Examples • STUDENT(studentID, studentName, lastName, birthDate, birthplace,...) • COURSE(courseID, courseName, creditHrs) • STUDENTCOURSE(studentID, courseID, grade) • DEPARTMENT(departmentID, departmentName) 11/17/2016 MGIS 301 Management Information Systems 48
- 49. Creating Relationships • DEPARTMENT(departmentID, departmentName) STUDENT(studentID, studentName, lastName, birthDate, birthplace,…, departmentID) • DEPARTMENT(departmentID, departmentName) COURSE(courseID, courseName, creditHrs, departmentID) 11/17/2016 MGIS 301 Management Information Systems 49 How to Insert the primary key of the relation on the one-side of the relationship into the relation on the many-side.
- 50. Merging Relations • DEPARTMENT(departmentID, departmentName) STUDENT(studentID, studentName, lastName, birthDate, birthplace,…, departmentID) COURSE(courseID, courseName, creditHrs, departmentID) 11/17/2016 MGIS 301 Management Information Systems 50 How to Reduce the number of repeating entities to one.
- 51. Physical Database Design 1. Create relations by using the RDBMS’s visual programming tools or SQL language 2. Establish relationships among relations by using the RDBMS’s visual programming tools or SQL language 3. Design data entry forms by using the RDBMS’s visual programming tools 4. Design queries by using the RDBMS’s visual programming tools or SQL language 5. Design regular reports by using the RDBMS’s visual programming tools 6. Design menus by using the RDBMS’s visual programming tools 11/17/2016 MGIS 301 Management Information Systems 51
- 52. Database Implementation 11/17/2016 MGIS 301 Management Information Systems 52
- 53. Database Management Systems (DBMS) 11/17/2016 MGIS 301 Management Information Systems 53
- 54. Components of a DBMS Create and change the logical structure of data Create-Read-Update-Delete Make queries Create and modify menus, forms and reports Data authorization Recovery and backup Structural changes 11/17/2016 MGIS 301 Management Information Systems 54 DBMSEngine Data dictionary Database Data definition language Data manipulation language Data administration tools Application generation tools Database Database
- 55. Client-Server Architecture Database server Application server Web server Internet Clients 11/17/2016 MGIS 301 Management Information Systems 55
- 56. Centralized Database Internet 11/17/2016 MGIS 301 Management Information Systems 56
- 57. Distributed Database Internet 11/17/2016 MGIS 301 Management Information Systems 57
- 58. Q&A ? 11/17/2016 MGIS 301 Management Information Systems 58
- 59. Next Week • We will have two online quizzes • The first due Tuesday, 10/25/2016 • The second due Thursday, 10/27/2016 • We will have a 2-page written assignment from Chapter 1 of our textbook. • We will discuss the issues related to Chapter 6 and Appendix C of our textbook. 11/17/2016 MGIS 301 Management Information Systems 59