title: select max value of a column in table with no rows
body: <p>I am using oracle database</p>
  
  <p>While inserting a row in a table, i need to find the max value of a column and increment it by 1, and use that value in row i am inserting.</p>
  
  <pre><code>INSERT INTO dts_route 
     (ROUTE_ID, ROUTE_UID, ROUTE_FOLDER)
  VALUES (
                          (SELECT MAX(ROUTE_ID) + 1 FROM  route) ,
                          ROUTE_UID,
                          ROUTE_FOLDER)
  </code></pre>
  
  <p>This works fine if their is at least one entry in table.
  But returns null when their are no entries in table.</p>
  
  <p>How can i get default value of 1 when their are no entries in table.</p>