title: SQL Deleting data based on max value of column
body: <p>I am looking to delete data from a table based on the max value of an index column - 23. Error received is 'In valid use of group function' </p>
  
  <p>Currently Have: </p>
  
  <pre><code>DELETE FROM Raw_Data 
  WHERE
      Raw_Data.Date_Index &gt; MAX(`Date_Index`) - 23
  </code></pre>
  
  <p>Thanks</p>