Lesson 02 (Creating Database & Tables)

 Creating Database-

Sql मैं सबसे पहले database बनाया जाता है

१.      startàall program -> MySql देकर Mysql चालू करें

२.      password पूछने पर abcd दें (हमने अपने कंप्यूटर पर sql का पासवर्ड abcd सेट कर रखा है

३.      create database  <database name> दें जैसे –

create database student;<enter>


उपरोक्त कमांड देने पर एक नई डेटाबेस फाइल तैयार हो जाएगी अब हम इसमें एक नई table create करेंगे –

Creating table –

तीन नई टेबल तैयार करें जिसमें निम्न फील्ड हों –

1-create table student (sid int, sname varchar(100), branch varchar(50), marks int)

इसमें निम्न रिकॉर्ड भरें –

insert into student values(1, ‘Lalit Kumr’ ‘IT’, 75);

(2, ‘Mahesh’, ‘IT’, 90)

(3, ‘Sagar’, CSE’, 92)

(4, ‘Arun’, CSE’, 45)

(5, ‘Shikha’, ECE’, 56)

(6, ‘Anand’, ‘ECE’, 78)

(7, ‘Parul’, ‘IT’ 82)

 

अब दूसरी table तैयार करें –

2- create table faculty(fid int, fname varchar(100) qualification varchar(50), deptid int);

इसमें निम्न डाटा भरें –

insert to faculty values(1, ‘Aman’, B.Tech’ 1)

(2, ‘Mohan’, ‘M.Tech’, 1)

(3, ‘Vishal’, ‘M.Tech’, 1)

(4,’Priya’, ‘Ph.D.’, 2)

(5, ‘Ravi’, ‘Ph.D’, 3)

(6, ‘Arti’, ‘M.Tech’, 2)

 

अब तीसरी टेबल तैयार करें –

3- create table department(deptid int, dname varchar(20);

इसमें निम्न डाटा भरें-

insert into department values(1, ‘IT’)

(2, ‘CSE’)

(3, ‘ECE’)

 

Showing Table Data-

select * from student;

select * from faculty;

select * from department;


Distinct Clause-

Table की लिस्ट देखते समय duplicate values को remove करता है

select distinct branch from student;

commint command-

mysql बंद करने से पहले database close करने के लिए इस कमांड का प्रयोग किया जाता है

commit;

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