title: PHP query mysql database in an efficient manner
body: <p>I am retrieving a lot of single data items from a mysql database and have constructed the code below whereby the variables for each data item is set to be identical to the ID that is queried. My problem is that the array contains some 50-100 elements and the query seems to be very slow as a result. I would very much appreciate if anyone can review the code and inform me if I can somehow optimize this such that it will execute faster. Thank you very much in advance.</p>
  
  <pre><code>        $idArray = [ // contains some 50-100 elements in total
            "BANANA",
            "APPLE",                 
            "COCONUT",       
            "PEAR",       
          ];
  
          foreach($idArray as $val) {
            $query = "SELECT * FROM {$tableName} WHERE ID = '{$val}'";
            $result = mysqli_query($conn, $query) or die('error');
            while($data = mysqli_fetch_array($result)) {
                $$val = $data["COINFO"];
            }
          }
  </code></pre>
  
  <p>Update: I have now tried to construct the query with the IN keyword instead but the query still seems to be executing very slowly on my server whereas there are no issues at all on my localhost. As such, I am wondering if there might be some other issue.</p>
  
  <p>Based on the comment below, I understand that the most optimal approach is to apply parameterized queries and bind_param and I would very much appreciate if someone can translate the above code to the new updated approach!</p>