Result set

[Amritpal Singh Moomie]

Hi i am building a basic login application with jdbc
But i am new to java ,
error with my code is that it will let me login only if enter the last record of the database ( Most recently added)

Can anybody help me what change should i make

 public String CheckValidUser()
{
	String query = "SELECT * from users";
	String result=" ";
	try
	{    Class.forName("com.mysql.jdbc.Driver").newInstance();
		 String url = "jdbc:mysql://localhost/moh";
		 conn = DriverManager.getConnection(url, " ", " ");
		 Statement st = conn.createStatement();
		 ResultSet rs = st.executeQuery(query);
		


		 while (rs.next())
		 {
					String name = rs.getString("name");
					String pass = rs.getString("pass");

				 if (loginname.equalsIgnoreCase(name) && password.equals(pass))
				 {
					  result= "success";
				 }
				 else
				 {
					  result ="fail";
				 }
						
		}
		 
		 conn.close();
		
	}
	 
	
	catch (ClassNotFoundException ex) {System.err.println(ex.getMessage());}
    catch (IllegalAccessException ex) {System.err.println(ex.getMessage());}
    catch (InstantiationException ex) {System.err.println(ex.getMessage());}
    catch (SQLException ex)           {System.err.println(ex.getMessage());}   
  
   return result;
   

}

[Paul Clapham]

You should change your code so it doesn't read every record in the database. As it is you do your comparisons on every record, but you only use the result after reading all the records. So you only use the result of the comparisons on the last record.

In fact you should only read records which match the user ID and password. If there are any such records then you can login. If there aren't any, then you can't login.

[Amritpal Singh Moomie]

How can i do comparison on every record and get result?

Do you have any code example or tutorial.


thanks

[Paul Clapham]

You would simply use a WHERE clause in your SQL statement. That should be covered very near the beginning of whatever you are using to learn SQL.

And when you do that, make sure to use a PreparedStatement to implement it. That's covered in the standard JDBC tutorial.

[Campbell Ritchie]

Moving to our databases forum.