The WHERE clause is used to filter records.It is used to extract only those records that fulfill a specified criterion.

SQL WHERE Syntax:

SELECT column_name(s)
FROM table_name
WHERE column_name = value;

Example:

In the given example, we have accepted the id from the user and retrieve the record of that user from the database.

import java.sql.*;
import java.util.*;

class RetrieveData 
{
    public static void main(String[] args) throws Exception
    {
        Scanner input=new Scanner(System.in);
        System.out.print("Enter id: ");
        int id=input.nextInt();
        Class.forName("com.mysql.jdbc.Driver").newInstance();
        Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "root" );
        Statement st=conn.createStatement();
        ResultSet rs=st.executeQuery("select * from data where id="+id+"");

        while(rs.next()){
            String name=rs.getString("name");
            String address=rs.getString("address");
            String contact=rs.getString("contactNo");
            String email=rs.getString("email");

            System.out.println(name+" \t "+address+" \t "+contact+" \t "+email);

        }
    }
}