create a statistics table using datetime MSSQL Query

Question

I have little table which gives me a very hard time:

Person    datetime1                   datetime2
Eric      2012-10-01 09:00:05.000     2012-10-01 22:00:00.000
Anna      2012-10-02 06:00:05.000     2012-10-03 12:00:05.000
Richard   2012-10-03 09:00:05.000     2012-10-04 02:00:05.000
Chuck     2012-10-01 12:00:05.000     2012-10-01 23:00:05.000

I am trying to write a query, which gives me statistics table. This table contains information about when a user logged in and out (daily granularity):

Date        logged_in  logged_off
2012-10-01  2          2
2012-10-02  1          0
2012-10-03  1          1
2012-10-04  0          1

According to my research, a pivot command could solve the problem?

select Person,
SUM(case when datetime1 = '2012-10-01' then 1 else 0 end) as [loggeed_in],
SUM(case when datetime2 = '2012-10-01'  then 1 else 0 end) as [logged_of]
from table
group by Person

This is not working... Do you have any ideas?

Answer 1

This will fix the current query, but don't know if it will solve the whole problem...

select Person,
SUM(case when convert(varchar(10), datetime1, 111) = '2012/10/01' then 1 else 0 end) as [loggeed_in],
SUM(case when convert(varchar(10), datetime2, 111) =  '2012/10/01'  then 1 else 0 end) as [logged_of]
from table
group by Person

EDIT: I believe this will better suit requirements...

SELECT 
    [Date] = dt,
    logged_in = (
        SELECT COUNT(*)
        FROM table1
        WHERE convert(varchar(10), datetime1, 111) = convert(varchar(10), dt, 111)),
    logged_off = (
        SELECT COUNT(*)
        FROM table1
        WHERE convert(varchar(10), datetime2, 111) = convert(varchar(10), dt, 111))
FROM (
    SELECT TOP 1000
        row_number() OVER(ORDER BY (SELECT 0)) AS N
        FROM master.dbo.syscolumns sc1, master.dbo.syscolumns sc2) tally
    CROSS APPLY(
        SELECT dt = DATEADD(dd, tally.N - 1, '2012-10-1')) tallydt
WHERE dt BETWEEN (SELECT MIN(dateadd(dd, -1, datetime1)) FROM table1) AND (SELECT MAX(datetime2) FROM table1)
GROUP BY dt 
ORDER BY dt

Answer 2

Here is the working solution:

WITH O AS (
SELECT
CAST([login Date & Time] AS DATE) loginDate
,COUNT(*) logined
 FROM table
 GROUP BY CAST([login Date & Time] AS DATE)
 ), C AS (
SELECT 
CAST([Close Date & Time] AS DATE) CloseDate
,COUNT(*) Closed
 FROM table
WHERE [Close Date & Time] IS NOT NULL
GROUP BY CAST([Close Date & Time] AS DATE)
 )
 SELECT
COALESCE(C.CloseDate, O.loginDate) TheDate
--,O.loginDate
--,C.CloseDate
,O.logined
,C.Closed
  FROM O 
  FULL JOIN C
 ON O.loginDate = C.CloseDate
 ORDER BY TheDate