title: updating multiple rows in one sql query
body: <p>I have to update an arbitrary number of rows for a list of customers, when reminders are sent out to them. I can achieve this through a foreach loop, but I am sure there must be a way of doing this with on query.</p>
  
  <p>This is what currently works</p>
  
  <pre><code>foreach($customer_id_arr as $c) mysqli_query($con,"UPDATE crm_customers SET customer_reminded=1 WHERE customer_id=$c");
  </code></pre>
  
  <p>How can I do that in one query?</p>