title: how i can SUM field values from two or more tables in php mysql
body: <p>I have six tables with each has two columns named (meal, cost).
  I can SUM meal of one table.
  but I want to SUM the total meal of every table.</p>
  
  <p>but like this.i have six tables. and I want to SUM the cost of every table at a time.</p>
  
  <pre><code>$qq="select SUM(cost5) as 'sumcost' from shawon"; 
  $res=mysqli_query($conn,$qq); $data=mysqli_fetch_array($res);  
  echo "&lt;div class='container'&gt;". "sum of cost: ".$data['sumcost']."&lt;/div&gt;";
  </code></pre>
  
  <p>is there any way  to do it?</p>