title: ORACLE SQL Running TOTAL and daytotal using window function
body: <p>From the EMPLOYEE table, I want to group the amount of records(employees hired) AND also have the running TOTAL per day.
  The format of the input is like this:</p>
  
  <pre>
  rownum  Hired_date_time
  1       1/10/2012 11:00
  2       1/10/2012 13:00
  3       20/11/2012 10:00
  4       20/11/2012 15:00
  5       20/11/2012 16:00
  6       30/12/2012 1:00
  </pre>
  
  <p>The desired output:</p>
  
  <pre>
  Hired_date.......Hired_per_day.........TOTAL_number_of_employees
  1/10/2012 ...................2 ........2
  20/11/2012 ..................3 ........5
  30/12/2012 ..................1 ....... 6
  </pre>
  
  <p>No problem for the GROUPING PER DAY:</p>
  
  <pre><code>select  trunc(Hired_date_time) as "Hired_date" , 
          count(*) as "Hired_per_day"
  from employee
  group by trunc(Hired_date_time)
  order by trunc(Hired_date_time);
  </code></pre>
  
  <p><em><strong>Question</em></strong>: how can I have a running total (in last column) using the window function </p>