PHP Mysqli Array in select html

Question

I’m a beginner in php and I’m developing a small system for my company and that already serves as a study, because I like this area, doubt is simple, I have the code below:

<?php
include('conn/conexao.php');
$edt = $_GET['edital'];
$sql = "SELECT * FROM edt_cadastro WHERE id = $edt";
$res = $mysqli->query($sql);
$num = $res->num_rows;

for ($i = 0; $i < $num; $i++) {
  $dados = $res->fetch_array();
  $arrRefs[$dados['id']] = $dados['ref0'];
}
?>

<label>Referências:</label>
<select name="ref" id="ref">
  <?php foreach($arrRefs as $value => $nome){
    echo "<option value='{$value}'>{$nome}</option>";
  }
?>
</select>

with this code it identifies the option of a previous select to load this select above (with jQuery), until then it works right, only that the value that comes from the database for this select, comes as an array example "1,2,3" i would like it to show me a list with 1 after 2, 3 and so on, in the bank is separated with comma "," (1,2,3) I have already tried to use the option explodes but then in the list only appears the last record in my example the number 3. could anyone help? thank you

Answer 1

I did, with the following Cod:

<?php           
include('conn/conexao.php');
$edt = $_GET['edital'];
$sql = "SELECT * FROM edt_cadastro WHERE id = $edt";
$res = $mysqli->query($sql);
$i = 0;
?>
<label>Referências:</label>
    <select name="ref" id="ref">
        <?php while ($row = $res->fetch_array()) {
            $referencias = $row['ref0'];
            $quantidade_ref = explode(",",$referencias);
            $total=count($quantidade_ref);
            $n = 0;
            while($n < $total) {
                $i++;
                echo '<option value="'.$i.'">'.$quantidade_ref[$n];
                $n++;
            }           
        }?>
    </select>