title: Show missing date from table in results
body: <p>I have one problem that it seems I can't solve, so I need your help.
  I have the below table of data. The ParientStatus and valueD are varchars and unfortunately, they cannot change (e.g. valueD to become datetime).</p>
  <p><a href="https://i.stack.imgur.com/JWvtg.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/JWvtg.png" alt="enter image description here" /></a></p>
  <p>and the query:</p>
  <pre><code>SET @enrolled = 0, @screened = 0;
  select
     MAX(IF(PatientStatus = 'Enrolled', @enrolled := @enrolled + 1, @enrolled)) AS EnrolledPatientsInitial,
     MAX(IF(PatientStatus = 'Screened', @screened := @screened + 1, @screened)) AS ScreenedPatientsInitial,
  valueD                                                                   as Date
  from table_name
  GROUP BY valueD;
  </code></pre>
  <p>What was requested from me, is to show one column with the dates and two more with the status of the patients that were enrolled or screened.
  If you ran the above code in this table, you will get the:</p>
  <p><a href="https://i.stack.imgur.com/XdHiP.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/XdHiP.png" alt="enter image description here" /></a></p>
  <p>which is correct for the data part, but the problem is that it needs to fill missing dates. For the specific example, I need to show also 2020-03 for which I have no data.</p>
  <p>I have read several issues here in stackoverflow, but none of them helped really.</p>
  <p>Can anyone help me with this?</p>
  <p>Thank you very much in advance.</p>