title: how do i divide and add column
body: <p>i have a list with peoples id and date, the list say when a person Entered to website (his id and date).
  how can i show for all the dates how many people enter the site two days in a row?</p>
  
  <pre><code>the data ( 30,000 like this in diffrent dates)
  01/03/2019  4616
  01/03/2019  17584
  01/03/2019  7812
  01/03/2019  34
  01/03/2019  12177
  01/03/2019  7129
  01/03/2019  11660
  01/03/2019  2428
  01/03/2019  17514
  01/03/2019  10781
  01/03/2019  7629
  01/03/2019  11119
  </code></pre>
  
  <p>I succeeded to show the amount of pepole enter the site on the same day but i didnt succeeded to add a column that show the pepole that enter 2 days in row.</p>
  
  <pre><code>date    number_of_entrance
  2019-03-01  7099
  2019-03-02  7021
  2019-03-03  7195
  2019-03-04  7151
  2019-03-05  7260
  2019-03-06  7169
  2019-03-07  7076
  2019-03-08  7081
  2019-03-09  6987
  2019-03-10  7172
  
  select date,count(*) as number_of_entrance
  fROM [finalaa].[dbo].[Daily_Activity]
  group by Date
  order by date;
  </code></pre>