PHP Get Number From Text Input And Compare To Decimal From DB

Question

I'm running some PHP that queries regularly from a MySQL DB.

In my DB I have a decimal (5,4) field with an assortment of values, some of them real integers and some of them decimal numbers.

I'd like to take an <input type="text"> tag from a form, $_GET the number the user entered, then compare it to a value in the DB.

Which of the three is the best way to go about this:

1. Convert the $_GET['user_value] variable to float, then compare to DB value.
2. Convert the $_GET['user_value] variable to integer, then compare to DB value.
3. Convert both $_GET['user_value] to strings, and then compare the two.

BTW: I need all the information after the decimal point.

MY CODE - $user_answer is the user's input, $correct_answer is DB Value

<?php
switch ($grid_type)
    {
        //If Single: Just Match Two Correct Answers
        case "single": 

            if($user_answer === $correct_answer)
            {
                $is_correct = 1;
            }
            else
            {
                $is_correct = 0;
            }

        break;

        //If Multiple: Check to see if user_answer Matches any of correct_answers
        case "multiple": 

            if($user_answer === $correct_answer OR $correct_answer_2 OR $correct_answer_3 OR $correct_answer_4 OR $correct_answer_5)
            {
                $is_correct = 1;
            }
            else
            {
                $is_correct = 0;
            }

        break;

        //If range: Check if user_answer is between the two range values
        case "range": 

            if($user_answer > $correct_range_bottom AND $user_answer < $correct_range_top)
            {
                $is_correct = 1;
            }
            else
            {
                $is_correct = 0;
            }

        break;

        default:
        "An Error Has Occured - All Of Your Base Are Belong To Us.";
    }
?>

Answer 1

@Tom None of the solution you listed are good. What you want to do is this:

get whatever value the user entered (using POST/GET request - post is prefered) then

$user_value = $_POST['user_value'];
if(is_numeric(str_replace('.','',$user_value))){
$user_value = sprintf('%0.4f',$user_value);
echo $user_value;
}else{
echo 'Wrong number entered';
}

then you compare with the value from the DB.