calculate total login logout time in mysql

Question

mysql> select * from timing;

+--------------+---------------------+-----------------+
| employeeIdNo | employeeLogTime     | employeeLogType |
+--------------+---------------------+-----------------+
|            1 | 2011-08-16 14:59:08 | login           |
|            1 | 2011-08-16 15:00:06 | logout          |
|            1 | 2011-08-16 15:14:51 | login           |
|            2 | 2011-08-16 15:15:00 | login           |
|            1 | 2011-08-16 15:59:01 | logout          |
|            2 | 2011-08-16 15:59:09 | logout          |
+--------------+---------------------+-----------------+

I want to display the total working time of employee using above data. so i want a mysql query to calculate the total time of(say) employeeIdNo=1. my table name is timing and employeeIdNo is the foreign key references from table employee. after calculation it should return me the totalLogTime value = 00:45:52(this is approx. value, i didnt calculated it exactly). please provide me with appropriate query. thanks in advance.

i tried this query.:-

mysql> SELECT 
  TIMEDIFF(FIRSTTIME.employeeLogTime,SECONDTIME.employeeLogTime) 
  FROM (
    (SELECT * FROM timing HAVING employeeLogTime = max(employeeLogTime)) as FIRSTTIME,     
    (SELECT * FROM timing ORDER BY employeeLogTime LIMIT 1,1) as SECONDTIME);
Empty set (0.01 sec)

its giving me empty set as shown above.

Answer 1

Couldn't you sum all times for a single user:

• for login (in milliseconds) call this A
• for logout (in milliseconds) call this B

and return B - A;

It's a bit ackward as a way to see it but gives much simpler sql queries. You also need to check that login and logouts have same number of occurences with this method.

Answer 2

Check dis

SELECT employeeIdNo ,sec_to_time(SUM(TIME))  FROM
(
    SELECT 
        TO_SECONDS(employeeLogTime     ) * -1 AS TIME
    FROM connection
    WHERE employeeLogType = 1
    UNION
    SELECT 
        TO_SECONDS(employeeLogTime     ) * 1  AS TIME
    FROM connection
    WHERE employeeLogType = 0
) t
;

Answer 3

select employeeIdNo,
sum(loginTimeInSec) as loginTimeInSec
from(
    select 
        e1.employeeIdNo, 
        TIME_TO_SEC(TIMEDIFF(e2.employeeLogTime,e1.employeeLogTime)) as loginTimeInSec
    from 
       timing e1 join timing e2
       on e1.employeeIdNo = e2.employeeIdNo
       and e1.employeeLogType = 'login'
       and e2.employeeLogType = 'logout'
       and e1.employeeLogTime < e2.employeeLogTime
       group by e1.id having min(e2.employeeLogTime - e1.employeeLogTime)
) temp
group by employeeIdNo;

Answer 4

Modify the employeeLogType column by changing login to 1 and logout to 0 . The table will look like:

mysql> select * from timing;
+--------------+---------------------+-----------------+
| employeeIdNo | employeeLogTime     | employeeLogType |
+--------------+---------------------+-----------------+
|            1 | 2011-08-16 14:59:08 | 1               |
|            1 | 2011-08-16 15:00:06 | 0               |
|            1 | 2011-08-16 15:14:51 | 1               |
|            2 | 2011-08-16 15:15:00 | 1               |
|            1 | 2011-08-16 15:59:01 | 0               |
|            2 | 2011-08-16 15:59:09 | 0               |
+--------------+---------------------+-----------------+

Query to display total time of all employees:

mysql> SELECT employeeIdNo, time(sum(employeeLogTime*(1-2*`employeeLogType`)))
FROM timing GROUP BY employeeIdNo;

Query to display total time of particular employee:

mysql> SELECT employeeIdNo, time(sum(employeeLogTime*(1-2*`employeeLogType`)))
FROM timing where employeeIdNo=(employeeIdNo) GROUP BY employeeIdNo;