title: How to UNION different datasets in SSRS?
body: <p>I have several datasets/tablixes on my report (e.g. seven datasets). All datasets have the same fields: First field is the primary key, the other fields are integer values. E.g:</p>
  
  <p><a href="https://i.stack.imgur.com/qc0pf.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/qc0pf.png" alt="enter image description here"></a></p>
  
  <p><a href="https://i.stack.imgur.com/JcKJ5.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JcKJ5.png" alt="enter image description here"></a></p>
  
  <p>and five other tables...</p>
  
  <p>Now what I want is to generate a new dataset, which UNION all datasets, then groups them by the ID and sums up all the fruits. Thus the new dataset looks like this:</p>
  
  <p><a href="https://i.stack.imgur.com/YRwoZ.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/YRwoZ.png" alt="enter image description here"></a> </p>
  
  <p>I Know that I could write a new SQL query which unions all the seven existent queries, but in my case this would be a very, very long query. So I wonder if this is possible by using pure SSRS functionality (e.g. expressions on calculated fields)?</p>