title: need eyes on a (to me) tricky sql
body: <p>In a mysql db, I have two tables:</p>
  
  <p><strong>prices</strong> - iid, trade_date, price</p>
  
  <p><strong>trades</strong> - iid, trade_date, nominal, price</p>
  
  <p>I am trying to create an aggregated, cumulative series with the dates from prices and the values calculated as sum(trades.nominal*prices.price) but nothing comes out the way I want.</p>
  
  <p><a href="http://sqlfiddle.com/#!9/a799b6/3" rel="nofollow noreferrer" title="SQL Fiddle 1">SQL Fiddle 1</a></p>
  
  <p><a href="http://sqlfiddle.com/#!9/d4a6d3/3" rel="nofollow noreferrer" title="SQL Fiddle 2">SQL Fiddle 2</a></p>
  
  <p>This is what I want to achieve:</p>
  
  <p><a href="https://i.stack.imgur.com/Qcbj9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/Qcbj9.png" alt="enter image description here"></a></p>
  
  <p>Any help greatly appreciated!</p>
  
  <p>PS. Had a typo. It said value = trades.nominal * trades.prices...it should be trades.nominal * prices.price.</p>