Institute of Southern Punjab, Multan

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1 Institute of Southern Punjab, Multan Mr. Muhammad Nouman Farooq BSC-H (Computer Science) MS (Telecomm. and Networks) Honors: Magna Cumm Laude Honors Degree Gold Medalist! Blog Url: noumanfarooqatisp.wordpress.com

2 Grading Policy Classification Assignments & Quizzes 6% (6 Marks in Total) Project & Presentation 9% (9 Marks) Midterm Exams 25% (25 Marks) Final Exam 50% (50 Marks) Total 100 % NOTE: 10% Marks will be Automatically given by Examination Deptt. on Attendance. 2

3 Academic Honesty Your work in this class must be your own If students are found to have collaborated excessively or to have cheated (e.g. by copying or sharing answers during an examination), all involved will at a minimum receive grades of 0 for the first violation Further violations will result in failure in the course 3

4 Few Things to Remember!! Attendance will be taken with in 15 minutes at the start of class Students are allowed to enter into class with in 30 minutes at the starting of class Zero tolerance policy on attendance, discipline of class during lectures! Assignments must be submitted on time, no late submissions In case of copied assignment both parties will be given zero! Projects, Presentation, Quizzes, Assignments, Class participation are very important. Don t miss your Classes, Quizzes, Presentations, Assignments and Projects! 4

5 Database Systems Introduction to Databases Lecture# 1 5

6 Recommended Books Modern Database Management by Jeffrey A. Hoffer, V. Ramesh and H. Topi 10th Edition Database Systems-A Practical Approach to Design, Implementation and Management by Thomas Connolly and Carolyn BEGG, 4th Edition Database Systems Design, Implementation, and Management-Carlos, Steven and Peter (9th Edition) Fundamentals of Database Systems by Elmasri and Navath 6

7 Reference Lab Manuals A guide to MySQL latest Edition by Muhammad Nouman Farooq A Guide To MySQL 8th Edition by Philip J. Pratt & Mary Z. Last 7

8 Lecture 1: Introduction to Databases Introduction to the Course Database Definitions Data & Information Data Models Flat File Vs Relational Database System Importance of Databases Introduction to File Processing Systems Advantages of Database Approach Database Users 8

9 Jonathan Abrams Friendster fails due to not optimized and efficient Database System Mark Zuckerberg Facebook did not fail due to optimized and efficient Database System 9

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11 Introduction to the Course 11

12 Introduction This course is first (fundamental) course on database management systems. The course discusses different topics of the databases. We will be covering both the theoretical and practical aspects of databases. As a student to have a better understanding of the subject, it is very necessary that you concentrate on the concepts as well as on the practical's which were done in the course. 12

13 Continued 1) Database design and application development: database? How do we represent a real-world system in the form of a 2) Concurrency and Robustness: How does a DBMS allow many users to access data concurrently, and how does it protect against failures? 13

14 Continued 3) Efficiency and Scalability: How does the database cope with large amounts of data? 4) Study of tools to manipulate databases: In order to practically implement, that is, to perform different operations on databases some simulators are required. The operations on databases include right from creating them to add, remove and modify data in the database and to access by different ways. 14

15 Database Definitions 15

16 Database Definitions An organized collection of information in computerized format. A collection of information organized and presented to serve a specific purpose A Computerized representation of any organizations flow of information and storage of data. 16

17 Continued The term database is often incorrectly referred to as a synonym for a database management system (DBMS). 17

18 Continued Each of the above given definition are correct, and describe database from slightly variant perspectives. From exam point of view, anyone will do. However, within this course, we will be referring first of the above definitions more frequently, and concepts discussed in the definition like, logically related data, shared collection should be clear. 18

19 Database Another Important thing that you should be very clear about is the difference between database and the database management system (DBMS). The database is the collection of data about anything, could be anything. Like cricket teams, students, busses, movies, personalities, stars, furniture, lab equipment, hobbies, hotels, pets, countries, and many more anything about which you want to store data. What we mean by data; simply the facts or figures Information: Data that have been processed in such a way as to increase the knowledge of the person who uses the data. 19

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21 Data and Information 21

22 Data and Information Data is the collection of raw facts collected from any specific environment for a specific purpose. Data in itself does not show anything about its environment, so to get desired types of results from the data we transform it into information by applying certain processing on it. Once we have processed data using different methods; than data is converted into meaningful form and that form of the Data is called information. 22

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24 Continued If we consider the data in the previous figure without the titles or the labels associated with the data (EmpName, age, salary) then; it is not much useful. However, after attaching these labels it brings some meanings to us, this meaningfulness is further increased when we associate some other labels, like the company name and the department name etc. So this is a very simple example of processing that we can do on the data to make it information. 24

25 Continued There could be infinite examples, there could be so many facts about each thing that we are storing data about. What exactly we will store depends on the perspective of the person or organization who wants to store the data. For example, if you consider food, data required to be stored about the food from the perspective of a cook is different from that of a person eating it. 25

26 Continued Think of a food, like, Karhahi Gosht, the facts about Karhahi Gosht that a cook will like to store may be, quantity of salt, green and red chilies, garlic, water, time required to cook and like that. Where as the customer is interested in chicken or meat, then black or red chilies, then weight, then price and like that. Well, definitely there are some things common but some are different as well. The thing is that the perspective or point of view creates the difference in what we store; however, the main thing is that the database stores the data using DBMS. 26

27 Database Management System The database management system (DBMS), on the other hand is the software or tool that is used to manage the database. Some tools are given below: 1. XAMPP (Navicat can be used as GUI of XAMPP) 2. Sequel Pro 3. Sequel Server 4. Microsoft Access 5. Oracle 27

28 Continued 28

29 Database Systems The term database system is a combination of database and the Database Management System (DBMS). So, database is collection of meaningful data/information, DBMS is a tool to manage this data, and both jointly are called database system. 29

30 Data Models 30

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48 Flat File Vs. Relational Database System 48

49 Flat File Vs Relational Database System A flat file database is a database designed around a single table. The flat file design puts all database information in one table, or list, with fields to represent all parameters. A flat file may contain many fields, often, with duplicate data that are prone to data corruption. 49

50 Continued If you decide to merge data between two flat files, you need to copy and paste relevant information from one file to the other. There is no automation between flat files. If you have two or more flat files that contain client addresses, for example, and a client moved, you would have to manually modify the address parameters in each file that contains that client s information. 50

51 Relational Database System A relational database, on the other hand, incorporates multiple tables with methods for the tables to work together. The relationships between table data can be ordered, merged and displayed in database forms. These tables are to be normalized up to 3 rd Normal Form (3-NF). 51

52 Importance Of Database 52

53 Importance Of Database Databases are important; why? Traditionally computer applications are divided into commercial and scientific (or engineering) ones. Scientific applications involve more computations, that is, different type of calculations that vary from simple to very complex. Today such applications exist, like in the fields of space, nuclear, medicine that take hours or days of computations on even computers of the modern age. 53

54 Continued On the other hand, the applications that are termed as commercial or business applications do not involve much computations, rather minor computation but mainly they perform the input/output operations. That is, these applications mainly store the data in the computer storage, then access and present it to the users in different formats (also termed as data processing) for example, banks, shopping, production, utilities billing, customer services and many others. 54

55 Continued From the previous examples, the commercial applications exist in the day to day life and are related directly with the lives of common people. In order to manage the commercial applications more efficiently databases are the ultimate choice because efficient management of data is the sole objective of the databases. So, such applications are being managed by databases even in a developing country like Pakistan. This way databases are related directly or indirectly almost every person in society. 55

56 Introduction to File Processing Systems 56

57 File Processing System 57

58 File Processing System 58

59 File Processing System 59

60 Continued The main point being highlighted is the program and data interdependence, that is, program and data depend on each other, well they depend too much on each other. As a result any change in one affects the other as well. 60

61 Continued The systems (even the file processing systems) are created after a very detailed analysis of the requirements of the organizations. But it is not possible to develop a system that does not need a change afterwards. There could be many reasons, mainly being that the users get the real taste of the system when it is established. 61

62 Continued Users tell the analysts or designers their requirements, the designers design and later develop the system based on those requirements. But when system is developed and presented to the users, it is only then they realize the outcome of the effort. 62

63 Continued Now, it could be slightly and (unfortunately) sometimes very different from what they expected or wanted it to be. So, the users ask changes, minor or major. Another reason for the change is the change in the requirements. For example, previously the billing was performed in an organization on the monthly basis, now company has decided to bill the customers after every ten days. 63

64 Continued Another major drawback in the traditional file system environment is the non-sharing of data. It means; if different systems of an organization are using some common data then rather than storing it once and sharing it, each system stores data in separate files. This creates the problem of redundancy or wastage of storage. 64

65 Continued The change in the data in one system sometimes is not reflected in the same data stored in other system. So different systems in organization; store different facts about same thing. This is inconsistency as is shown in figure below. 65

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67 Advantages of Database Approach 67

68 Database System Environment It will be helpful to reiterate our database definition here, that is, Database is a shared collection of logically related data, designed to meet the information needs of multiple users in an organization A typical database system environment is shown in the figure on next slide. 68

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70 Continued The figure shows different subsystem or applications in an educational institution, like library system, examination system, and registration system. There are separate, different application programs for every application or subsystem. However, the data for all applications is stored at the same place in the database and all application programs, relevant data and users are being managed by the DBMS. 70

71 1-Data Sharing The data for different applications or subsystems is placed at the same place. This introduces the major benefit of data sharing. That is, data that is common among different applications need not to be stored repeatedly, as was the case in the file processing environment. For example, all three systems of an educational institution shown in figure need to store the data about students. 71

72 Continued Now the data like registration number, name, address, father name that is common among different applications is being stored repeatedly in the file processing system environment, where as it is being stored just once in database system environment and is being shared by all applications. 72

73 2-Data Independence Data and programs are independent of each other, so change in one has no or minimum effect on other 3-Controlled Redundancy Means that we do not need to duplicate data unnecessarily; we do duplicate data in the databases, however, this duplication is deliberate and controlled. 73

74 4-Data Integrity: Very important feature; means the validity of the data being entered in the database. Since the data is being placed at a central place and being managed by the DBMS, so it provides a very helpful to check or ensure that the data being entered into the database is actually valid. We can also define it as Level of Correctness of Data. 74

75 5-Better Data Security All application programs access data through DBMS, So DBMS can very efficiently check that which user is performing which action and accessing which part of data. So, A DBMS is the most effectively control and maintain security of Data stored in a database. 75

76 6-Faster Development of new Applications The database environment allows us faster application development because of its many reasons. As we know that database is designed focusing the conclude result to meet the expectations of the client. 76

77 7-Better Concurrency Control Concurrency means the access of database form as number of points simultaneously. Concurrency Control means to access the database in such a way that all the data accesses are completed correctly and transparently. One example of controlled concurrency is the use of ATM Machine for withdrawal of money (cash). All ATM machines of a bank are interconnected to a central database system worldwide, so that a user can access its account from anywhere in the world and can get cash from any ATM terminal. 77

78 Continued As there are thousands of ATM terminal across the world for a specific bank so as a result thousands of user process and access the bank s database. All this process is managed concurrently using the database systems and is done in such an efficient manner that no two user face any delay in the processing of their requests. 78

79 8-Better Backup and Recovery Facility Some time happens that a database which was in use and very important transactions were made after the last backup was made, all of a sudden due to any disastrous situation the database crashes (improper shutdown, invalid disk access, etc.) Now, In such a situation the database management system should be able to recover the database to a consistent state so that the transactions made after the last backup are not lost. 79

80 Database Users 80

81 Database Users Users of Database Systems: 1) Application Programmers 2) End Users Naive User Sophisticated User 81

82 1) Application Programmers This category of database users contains those people who create different types of database application programmer. Application programmers design the application according to the needs of the other users of the database in a certain environment. Application programmers are skilled people who have clear idea of the structure of the database and know clearly about the needs of the organizations. 82

83 2) End Users Second category of the Database users are the end users, this group of users contains the people who use the database application programs developed by the Application programmers. This category further contains two types of users: Naïve User This category of users is that category who simply use the application database programs created by the programmers. 83

84 Continued Sophisticated User This type of users has some additional rights over the Naïve users, which means that they can access the data stored in the database any of their desired way. They can access data using the application programs. Moreover such users should be skilled enough to be able to get data from database without damaging the data in database. 84

85 Recommended Readings Chapter 1 from: - Database Systems-A Practical Approach to Design, Implementation and Management by Thomas Connolly and Carolyn BEGG, 4th Edition (Page No ) Modern Database Management - 8th Edition by Jeffery A. Hoffer, Prescott and McFadden (Page No ) 85

86 Summary of Lecture Lecture 1 Database Definitions Data & Information Importance of Databases Data Models Flat File Vs Relational Database System Introduction to File Processing Systems Advantages of Database Approach Database Users 86

87 END OF LECTURE 1 87

Institute of Southern Punjab, Multan

Institute of Southern Punjab, Multan Mr. Muhammad Nouman Farooq BSC-H (Computer Science) MS (Telecomm. and Networks) Honors: Magna Cumm Laude Honors Degree Gold Medalist! Blog Url: noumanfarooqatisp.wordpress.com