JDBC Connectivity using Eclipse

 import java.io.BufferedReader;

import java.io.InputStreamReader;

import java.sql.*;  


public class mysqlconn {

public static void main(String args[]){  

try{  

Class.forName("com.mysql.cj.jdbc.Driver");  

Connection con=DriverManager.getConnection(  

"jdbc:mysql://localhost:3306/demo","root","root");  

Statement stmt=con.createStatement();  

ResultSet rs=stmt.executeQuery("select * from emp");  

while(rs.next())  

System.out.println(rs.getInt(1)+"  "+rs.getString(2)); 

int i=17;

String name1="smita";

int did=4;

int credit =2000;

InputStreamReader r1=new InputStreamReader(System.in);    

BufferedReader br1=new BufferedReader(r1);            

System.out.println("Enter your id");    

try {

name1=br1.readLine(); 

}catch(Exception E) {}

i=Integer.parseInt(name1);

InputStreamReader r=new InputStreamReader(System.in);    

BufferedReader br=new BufferedReader(r);            

System.out.println("Enter your name");    

try {

name1=br.readLine(); 

}catch(Exception E) {}

String sql = "INSERT INTO emp VALUES ("+i+","+"'"+name1+"'"+","+did+","+credit+")";

 

PreparedStatement statement = con.prepareStatement(sql);

 

int rowsInserted = statement.executeUpdate();

if (rowsInserted > 0) {

    System.out.println("A new user was inserted successfully!");

}


sql="UPDATE emp SET ename='Gaurav' WHERE eid=4";

 

statement = con.prepareStatement(sql);

 

int rowsUpdated = statement.executeUpdate();

if (rowsUpdated > 0) {

    System.out.println("An existing user was updated successfully!");

}

InputStreamReader r4=new InputStreamReader(System.in);    

BufferedReader br4=new BufferedReader(r4);            

System.out.println("Enter  id of employee which is to be deleted: ");    

try {

name1=br4.readLine(); 

}catch(Exception E) {}

i=Integer.parseInt(name1);

sql = "DELETE FROM emp  WHERE eid="+i;

 

statement = con.prepareStatement(sql);

int rowsDeleted = statement.executeUpdate();

if (rowsDeleted > 0) {

     System.out.println("A user was deleted successfully!");

}

}catch (Exception e) {}

}

}


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