Login - var compare to database?

Hey all I've made a very simple login system, and have a registration screen which saves the required data to a Microsoft access database.

What I'm struggling/curious about is how to compare what the user inputs to what exists in the database

Here is my current login code (at the moment I just have a var that can be defined in the code for the users name & surname):

 var mySkin : GUISkin;
 
 var GeneralWidth = 73; // Width for most bottons should be the same. Use GeneralWidth. Use there custom Width if needed.
 
 var LoaderHeight = 10;
 var LoaderWidth = 10;
 
 var LogHeight = 101;
 var LogWidth = 163;
 
 var PlayerUsername = "Test1";        //var for user name
 var PlayerPassword = "12345";        //var for user password
 
 var UserHeight = 35;
 var UserWidth = 1;
 
 var PassHeight = 65;
 var PassWidth = 1;
 
 var GameOwner = "";                //shows current user input for name
 var GameOwnerPassword = "";        //shows current user input for password
 
 var UsernameCORRECT = false;
 var PasswordCORRECT = false;
 
 function Update (){
     // Updates each frames and checks if the TextArea is equal to the username we want
     if (PlayerUsername == GameOwner){
             UsernameCORRECT = true;
     }
         
     else {
             UsernameCORRECT = false;
     }
         
     // Updates each frames and checks if the TextArea is equal to the password we want    
     if (PlayerPassword == GameOwnerPassword){
             PasswordCORRECT = true;
     }
     
     else {
             PasswordCORRECT = false;
     }
 }
 
 function OnGUI () {
     // Assign a skin to you menu
     GUI.skin = mySkin;
     
     // Background box
     GUI.Box (Rect (LoaderHeight,LoaderWidth,220,120), "Log-in");
     
     //Text area for the username
     PlayerUsername = GUI.TextArea (Rect(GeneralWidth,UserHeight,100,20),PlayerUsername);
 
         
     //Text area for the password
     PlayerPassword = GUI.TextArea (Rect(GeneralWidth,PassHeight,100,20),PlayerPassword);
     
     
     // Loads level (0) - customize in build settings
     if (GUI.Button (Rect (LogWidth,LogHeight,60,25), "Log-In")) {
         
         if(UsernameCORRECT == true){
         
             if(PasswordCORRECT == true){
             
         Application.LoadLevel (2);
         
             }
             
         }
     }
     else
         {
         Debug.Log("Username or Password was Incorrect");        
         }
 }