User Evaluation System with unique notes

I am developing an evaluation system for my team's employees. In this case, this system would be done as follows. A user who evaluates can do 5 ratings only. These 5 ratings may be in grades 1-5 and these grades will not be repeated. In other words, the Evaluating User will give the grade of 5 to another collaborator, but he will not be able to repeat grade 5 to another collaborator.

In this case, I used this test in SQL to return the notes that have already been given.

SELECT [nota] FROM [dbo].[tb_result_destaque] WHERE [usr_reg] = 
'usuario' 

In the case, I threw this query into PHP and did a test to read all the notes that have already been assigned and tried to play it inside an array and using explode to make the comparison. If the note has already been given, it would leave a disable in the select HTML option.

<option disabled value="1">1</option> 

But not even this part is coming, since with the test, it reads all the notes but I can not pass all the notes out of the While Here's a snippet of the code I'm trying to work on

 $result = $sql->execute($consultaNota); 
   while(!$result->EOF) { 
       $nota = $result->Fields['nota']->Value;
         $notaArray = array($nota); 

         $result->MoveNext(); 
   } 

In the case I put an explode and a foreach between the array and the movenext and tried to pass the data out, but as I said none worked. I populated the bank and in case the user had already given the 1.4 and 5 notes when I need to pass out the Loop it just shows the 1.

In case what do I need to do?