1. Database Management System
Lessson-01 Date: 09/05/2018
Chapter-06
Database Management System

2. Todays Lesson………….
Concept of Database

3. What is database? Organized collection of meaningful data
Collection of related data about any object.
Sl.No
Name
Roll
Class
form 1
Samin 59 VI A 2
Wasif
101
VII B 3
Raisa 67
VIII 4
Xima 45 IX 5
Sumaiya 65 X 6
Fahimul 89
XII

4. Basic elements of a database
Record
Field
Sl.No
Name
Roll
Class
form 1
Samin 59 VI A 2
Wasif
101
VII B 3
Raisa 67
VIII 4
Xima 45 IX 5
Sumaiya 65 X 6
Fahimul 89
XII
Table

5. Entity, Attribute and values
An object which is distinguishable from other object.
Example: Student, Book, Product etc.
Attribute:
Elements that expressses characteristics of an entity.
Example: Name, Roll, Class, Address etc.

6. Attribute
Class
Roll
Name
Address
Entity
Student

7. Summary Define database Define field and record.
Deifne entity and attribute
Difference between field and record

8. Sample MCQ Smallest unit of database is…… Ans: field
Number of field in a database is……
Ans: Unlimited
Every element of an entity is called…..
Ans: Attribute

9. HW What is Database? Draw a database and identify different elements.
Define entity attribute and value of attribute with example.
Explain difference between field and record.

10. Todays lesson………
KEY Field

11. What is key field?
The unique field of a database which is used to search or retrieve record from database is called key field.
Roll, Emp_id, Regno, Social Security Number, IDNo etc may be the key fields

12. Types of Key field
Primary Key
Composite Primary Key
Foreign Key

13. Primary Key
The key field which is used to uniquely identify record from a database table is called primary key.
Primary key
Emp_ID
Name
Designation
Salary
120956
Sajjad Khan
Professor
120957
Sadia Islam
Associate Prof.
120856
Amzad hossain
Assistant Prof
130957
Samsul Arefin
Lecturer

14. Composite Primary Key
Composite primary key is defined as the key field which is formed by combining two or more fields of a database to uniquely identify record from a database.
Composite Primary key
Roll
Board
Name
Session
120956
Dhaka
Maisha Mehzabin
Barishal
Tanvir Rahman
120856
Jashore
Sadman Sakib
Rajshahi
Samin Yasar
Cumilla
Monira Sultana

15. Foreign Key
In relational database, primary key of one table is used as general key of another table. Primary key of first table is called foreign key of second table.
Primary key/Foreign Key
Student
Result
Roll
Name
Address 60
Maisha
Uttara 61
Tanvir
Gazipur 62
Sadman
Gulshan 63
Samin
Banani
Roll
Marks
GPA 60
900
5.00 61
850
4.50 62
950 63
980

16. DBMS
Collection of data and set of rules that are used to access those data is called DBMS.
Application-01
Application-02
Application-03
DBMS
FILE

17. Different types of Database Management software
MySQL
SQLite
SQL Server
MS Access
Oracle
dBASE
FoxPro

18. Main functions of DBMS To create new database
To insert new record into database
Error correction of data
To Remove unnecessary record
To arrange the records on the basis of any field.
To search specific record.
To establish link/relation with many tables
To prepare customize form
To prepare formatted report

19. Uses of DBMS DBMS is used in………. Office management
Bank/Insurance to maintain customer account
Chain shop(buy, sell, profit , loss calculation)
Educational institution(Exam result, routine, stdinfo etc)
Airlines, Railway,Hotel(reservation, schedule maintanance)
Hospital, research/survey etc
Large organization To store records of employees

20. Emphasize should be given on the Following points before creating database
Objective of the database
Nature of database user(General, Online, Application, DBA)
Number of table
Number of fields in each table
Data type
Field length
Field property etc

21. THANK YOU

22. Lesson-03
Data type

23. In every field of a database table we can store specific type of data as per our requirement.
The type of data is defined while designing table as shown in the following figure.
Data types

24. Stdinfo table

25. Brief description of data types
Auto number
It is used for series type data.
Advantage: Data is entered automatically after the entry of previous record.(No manual entry)
Example: Sl.No, empid, roll, regno etc.
Text
It is used for character (Letter, digit, symbol) based data. Up to 255 characters can be written in this field.
Example: Name, F_Name,Designation, Address etc.

26. Brief description of data types
Number
It is used for Numeric data entry. Both integer and whole number can be used but no letters is allowed here.
Example: Marks, GPA, Mobileno etc.
Currency
It is used for money related data
Example: any kind of fees, Salary, price etc

27. Brief description of data types
Date time
It is used for time and date related data.
Example: DOB,J_Date, Admission_Date etc.
Types
General date: 10/30/2018 5:34:23 PM
Long Date: Tuesday, June 19, 2007
Medium Date: 19-Jun-07
Short Date: 6/19/2007

28. Brief description of data types
Logical
It is used for yes/no, true/false, on/off type data.
Size of this field is 1
Example: present-absent, married-unmarried, skilled-unskilled, passed-failed etc.
Memo
It is used for the field having huge characters as field value. Maximum characters are allowed here.
Example: Product description, work experience, job description etc.

29. Brief description of data types
OLE Object
Full form of OLE is Object Linking and Embedding. It is used to add different objects with the database. Objects may be doc, xls,pdf,html, ppt,jpg,mp3, mp4 etc.
Example: photo, markssheet, report etc.
Hyperlink
It is used to establish link between webpage and database.
Example: webaddress of any organization

30. Brief description of data types
Look up wizard
This data type is used for inputting data from prepared list.
Example: class, district, form, blood group, country, group etc.

31. Vacation work
Prepare 30 MCQ from this chapter

38. END

39. Query What is query? To search necessary data from one or more
table under specific condition is known as query.
Query command is used to search, retrieve,
display and print information.
As for example the expression Roll=224 can be
created to search record of a student from
student table whose roll is 224.

40. Types of query Query may be of different types. Such as:- Select Query
Parameter query
Crosstab Query
Maketable Query
Action Query

41. Select Query
The query which is based on field and record of a data table is known as Select query. Let we want to display all the records of student table, so the respective select query command will be as follows:-
SELECT *
From Student;

42. Parameter Querie
The query that is performed by entering parameter value through dialog box is called parameter query.

43. Crosstab query
The query which is performed by imposing condition and represent data as summary report is known as crosstab query. A crosstab query is a matrix, where the column headings come from. the values in a field.
Make table query:
The query can be used to join several tables or return a subset of columns or rows from the original data in the database. Make table query produces a new table that contains the desired for which the query is made.

44. The above three statements and their syntaxes are stated in the following table.
Action query:
Action queries are queries that make changes to many records at once. They are used to delete records, to update records (that is, to change values in them), to create new tables, to delete tables and to launch queries that accept a user-supplied parameter.
The above three statements and their syntaxes are stated in the following table.
Statement
Syntax
INSERT
INSERT INTO Table_name (fiels1, field2, field3…)
VALUES (Val1, val2, val3…);
DELETE
DELETE FROM Table_name
WHERE some_field=some_val;
UPDATE
UPDATE table_name
SET field1=val1, field2=val2

45. QUERY language
Query language (QL) refers to any computer programming language that requests and retrieves data from database and information systems by sending queries.
There are three types of query languages.Such as:-
QUEL (Query Languages)
QBE (Query BY Example
SQL (Structured Query Language)

46. SQL
SQL (Structured Query Language) is a programming language designed for managing data in relational database management systems (RDBMS).

47. There are two types of SQL. Such as:- DDL (Data Definition Language)
DML( Data Manipulation Language)
DDL: A data definition language or data description language (DDL) is a syntax similar to a computer programming language for defining data structures, especially database schemas.
Following statements are used under DDL.
CREATE table
DROP table
ALTER table

48. 1. SQL CREATE TABLE Statement
The CREATE TABLE statement is used to create a new table in a database.
Syntax
CREATE TABLE table_name (     column1 datatype,     column2 datatype,     column3 datatype,    .... );

49. Following 4 tasks are considered as Data Manipulation.
SQL inDML
Following 4 tasks are considered as Data Manipulation.
Retrieve
Insert
Delete
Update

50. Retrieve data from database table:
Example 1:Write down SQL command to retrieve all the records from
employee table.
Soln:
SELECT *
FROM employee;

51. SELECT Name, Designation, Salary FROM employee; Output:
Example 2: Write down SQL command to retrieve Name, Designation and Salary of the employees from the employee table.
SELECT Name, Designation, Salary
FROM employee;
Output:
Example 2: Write down SQL command to retrieve Name, Designation and Salary of the employees from the employee table.
SELECT Name, Designation, Salary
FROM employee;
Output:

52. where address="uttara";
Example 3: Write down SQL command to retrieve records of the employees from the employee table whose address is at Uttara.
SELECT *from employee
where address="uttara";
Example 4: Write down SQL command to retrieve records of the employees from
the employee table who’s Salary is more than Tk and skill is Good.
SELECT *FROM employee
where (Salary>50000) and (skill="Good");

53. 1.SQL INSERT Statement.
The INSERT INTO statement is used to insert new records in a table.
Syntax: INSERT INTO table_name (column1,column2,column3,...) VALUES (value1,value2,value3,...);
Example: INSERT INTO student (StdName, Roll,Class, Address,DOB,Contact) VALUES (‘Tajwar',‘XII-Sc-A’.,’H#14, R#12, Sector#6, Uttara‘,10-Jan-2000);
2. SQL UPDATE Statement The UPDATE statement is used to update existing records in a table. Syntax UPDATE table_name SET column1=value1,column2=value2,... WHERE some_column=some_value;
Example: UPDATE Student
SET Class=“XII-Sc-B”
WHERE Roll=101;

54. SQL DELETE Statement
The DELETE statement is used to delete rows in a table. Syntax: DELETE FROM table_name WHERE some_column=some_value;
Example: DELETE FROM Student WHERE Roll=105;

55. Example: UPDATE Student SET Class=’XII’, Form='A' WHERE Roll=101;
3. SQL DELETE Statement The DELETE statement is used to delete rows in a table. Syntax: DELETE FROM table_name WHERE some_column=some_value;

56. Types of Database Relationships
There are four different types of database relationships, each named according to the number of table rows that may be involved in the relationship. Each of these four relationship types exists between two tables. These are:-
One to One relation
One to Many relation
Many to One relation
Many to Many relation.

57. One to one

58. One to Many

59. Many to One

60. Many to Many
It occur when each record in the first table corresponds to one or more records in the second table and each record in the second table corresponds to one or more records in the first table. It is very complex to establish many to much relation

61. Other examples of Many to Many relation
A author has contributed to many book, a book is written by many authors
In a Sales database, each product belongs to one or more groups, and each group contains multiple products
In banking, a customer can have different accounts, and an account can belong to different customers.
In insurance, a customer (or household) can have different policies, but a policy can support multiple customers (or households). In many businesses, a parent customer can have subsidiaries.

62. Wish You all the best A+