Question

I have a query for sql server that returns this “table” below. The query uses some joins to link the data together. What I’m trying to do is add up each interviewers logged in time and in addition turning NULL into the time at this moment.

INTERVIEWER NUM_COMPLETES   projectId   loginDateTime   logoutDateTime
002                2    43407      2011-09-20 22:59:15.193  NULL
004                1    43407      2011-09-20 23:06:32.287  NULL
007                1    43407      2011-09-20 23:02:30.930  NULL
007                1    43407   2011-09-20 00:37:01.213 2011-09-20 01:15:00.197
010                3    43407      2011-09-20 23:04:46.547  NULL
013                1    43407   2011-09-20 00:36:16.923 2011-09-20 01:14:59.440
029                3    43407   2011-09-20 22:58:55.083 2011-09-20 23:30:56.987
029                3    43407   2011-09-20 23:31:05.243 2011-09-21 00:02:27.560
029                3    43407     2011-09-21 00:02:55.527   NULL
032                1    43407     2011-09-20 22:59:19.590   NULL
036                1    43407     2011-09-20 23:02:33.497   NULL
041                1    43407     2011-09-20 22:59:55.020   NULL

Should turn into

INTERVIEWER NUM_COMPLETES   projectId   TotalTime
002                2      43407            8
004                1      43407            10
007                1      43407            4
008                1      43407            7

It’s like a date diff that is summed up per interviewer.

Here is a sample + sanitized tsql statement that I am using

SELECT tbl1.INTERVIEWER, tbl1.NUM_COMPLETES, tbl2.projectId, tbl2.loginDateTime, tbl2.logoutDateTime
FROM 
(
SELECT k_Id, FirstName AS INTERVIEWER, COUNT(result) AS NUM_COMPLETES
FROM db1_table, db2_table
WHERE k_Id=Interviewer
GROUP BY k_Id, FirstName, result
) AS tbl1
INNER JOIN
(
SELECT projectId, loginDateTime, logoutDateTime, userId
FROM session_tbl
WHERE loginDateTime >= '2011-09-20 0:0:0.0' AND projectId = '43407'
) AS tbl2
ON tbl1.k_Id=tbl2.userId
ORDER BY INTERVIEWER

Thank you for any help — I’ve been struggling with this the past couple of days!

Answer 1

You should be able to use a standard GROUP BY to do this.

select
    userId, 
    projectId, 
    sum(datediff(hour, loginDateTime, isnull(logoutDateTime, getdate()))) as totalHours

from session_tbl

group by userId, projectId