title: SQL Join of multiple tables by single column without duplicates and fill up other columns
body: <p>I have twelve tables (for twelve months) that have same columns (Contract_number, Days, etc...).
  Whan I need is to select all entries from column Contract_number for all twelve months, and than have 12 columns with days from each table.</p>
  
  <p>Table January</p>
  
  <pre><code> Contract Number # Days
   1                 10
   2                 20
  </code></pre>
  
  <p>Table February</p>
  
  <pre><code> Contract Number # Days
   1                 20
   2                 40
   3                 10
  </code></pre>
  
  <p>Table March</p>
  
  <pre><code> Contract Number # Days
   2                 50
   3                 70
   4                 5
  </code></pre>
  
  <p>Output table should look like this </p>
  
  <pre><code> Contract Number # Days January # Days February # Days March
   1                   10             20              NULL
   2                   20             40               50
   3                  NULL            10               70 
   4                  NULL           NULL              5
  </code></pre>
  
  <p>I have tried with this query, however I get three columns with Contract_Number</p>
  
  <pre><code> SELECT dbo.[January].*, dbo.[February].*, dbo.[March].*
  FROM dbo.[January]
      FULL JOIN dbo.[February]
          ON dbo.[February].CONTRACT_NUMBER = dbo.[January].CONTRACT_NUMBER
      FULL JOIN dbo.[March]
          ON dbo.[March].CONTRACT_NUMBER = dbo.[February].CONTRACT_NUMBER
  </code></pre>
  
  <p>I have tried searching all join questions here, but none of them actually covers such scenario.</p>