title: Left Outer Joining Tables with Multiple Property Keys
body: <p>Long time lurker, first time poster.</p>
  
  <p>I have two tables 'case' and 'case_char'.</p>
  
  <p><strong>case</strong></p>
  
  <pre><code>case_id | status | date  
      1   | closed | 01/01/2014  
      2   | open   | 02/01/2014   
  </code></pre>
  
  <p><strong>case_char</strong>  </p>
  
  <pre><code>case_id | property_key |  value  
     1    | email        | xx@xx.com  
     1    | phone        | 1234567  
     2    | email        | x2@xx.com  
     2    | phone        | 987654  
     2    | issue        | Unhappy  
  </code></pre>
  
  <p>Say I want to return the 'issue' for each case. Not all cases have issues so I will need to do a left outer join. Unfortunately it is not working for me, it is returning only cases with the 'issue' characteristic. I need it to return all cases regardless of whether the 'issue' characteristic exists for a case in the case_char table. </p>
  
  <p>Below is an example of the way I have written the code ( bearing in mind I am using an Oracle DB). </p>
  
  <p>Could any of you whizzes help a brother out?</p>
  
  <pre><code>SELECT   c.case_id, char.value  
  FROM  case c, case_char char  
  WHERE c.case_id = char.case_id (+)  
  AND char.property_key = 'issue'  
  </code></pre>