title: Find duplicate items in a column Oracle SQL
body: <p>I have searched for <a href="https://stackoverflow.com/questions/4522431/find-duplicate-entries-in-a-column">Find duplicate entries in a column</a> and <a href="https://stackoverflow.com/questions/13776123/oracle-find-duplicate-rows-in-select-query">Oracle: find duplicate rows in select query</a>, but couldn't seem to get any answer...</p>
  
  <p>I have some data that looks like this</p>
  
  <pre><code>columnA    columnB    columnC
  1111111    emailID1   true
  1111111    emailID2   false
  1111222    emailID3   true
  1111339    emailID4   true
  2384398    emailID5   true
  </code></pre>
  
  <p>I would like to only display these column that has the same values in columnA but can be different in columnB and/or C:</p>
  
  <pre><code>columnA    columnB    columnC
  1111111    emailID1   true
  1111111    emailID2   false
  </code></pre>
  
  <p>Using the having >1 doesn't really seem to capture this, any ideas?
  Thanks.</p>