How to make a change to a database cell?

Question

PHP

Help me figure out how to write the code correctly? There is an id variable, suppose it has a value of 11-2 , there are three columns in the database called count1, count2, count3.
It is necessary to read the value in the database in line 11 in the count2 column and add the value of the count variable.

function change(){
    $conn = connect();
    $data = $_POST ['getdata'];
    $stmt = $conn->prepare("UPDATE `sortlist` SET `count$id[1]` ='count$id[1]' + ? WHERE `id`= ? ;");
    $stmt->bind_param('is', $count, $id[0]);//Привязка параметров integer,string
    foreach ($data as $value) {
        $id = $value["id"];        
        $id=explode("-", $id);
        $count = $value["count"];
        $stmt->execute();
    }

Answer 1

Using dynamic queries can lead to a security breach, so I can advise the following approach to this problem:

$stmt = $conn->prepare(
  "UPDATE `sortlist` 
  SET 
    `count1` ='count1' + ? ,
    `count2` ='count2' + ? ,
    `count3` ='count3' + ? 
  WHERE `id`= ? ;"
);
$stmt->bind_param('iiis', $count1, $count2, $count3, $row);

foreach ($data as $value) {
  list($row, $col) = explode("-", $value['id']);
  
  $count1 = 0;
  $count2 = 0;
  $count3 = 0;
  
  $column = "count" . intval($col); 
  $$column = $value["count"];
  
  echo "$count1, $count2, $count3, $row";
  
  $stmt->execute();
}

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