How to compute the aging time from datetime data's

Databases
1

Hi…

I have datetime data in my table kanban_data field chemicalweighing_dateEntry.
sample data of chemicalweighing_dateEntry:

2012-03-20 08:12:55
2012-03-20 08:16:44
2012-03-20 08:19:28
2012-03-20 08:20:17
2012-03-20 08:27:52
2012-03-20 08:28:36
2012-03-20 08:29:03
2012-03-20 08:31:47
2012-03-20 08:32:24
2012-03-20 08:35:45

I need to get the aging of chemicalweighing_dateEntry.

using this formula:

Aging time (00:00:00) = now() - SUM of chemicalweighing_dateEntry.

I don’t know what mysql function should I used to get the aging time.
Thank you

2

try this –

SELECT SEC_TO_TIME(
         TIME_TO_SEC( CURRENT_TIMESTAMP ) -
         TIME_TO_SEC( SUM(chemicalweighing_dateEntry) )
             ) AS aging_time

that would make perfect sense if only it were possible to sum datetimes!!! (hint: it isn’t)

just what exactly does “sum of chemicalweighing_dateEntry” actually mean?

3

I tried it:


SELECT SEC_TO_TIME(
         TIME_TO_SEC( CURRENT_TIMESTAMP ) -
         TIME_TO_SEC( SUM(chemicalweighing_dateEntry) )
             ) AS aging_time FROM kanban_data;

the output display is: NULL

Thank you

4

I mean total of chemicalweighing_dateEntry.

Thank you

5

you can’t add datetimes

you’re welcome

6

I tried this:


SELECT sec_to_time((SUM(time_to_sec(chemicalweighing_dateEntry))) - TIME_TO_SEC (NOW())) FROM kanban_data;

I’m not sure if my output : 95:24:15 is correct.

Thank you

7

just what exactly does “sum of chemicalweighing_dateEntry” actually mean?

HINT: YOU CAN’T ADD DATETIMES

8

Yes,

I just want to know if my query is correct.

Thank you

9

no

it isn’t

you’re welcome

10

What’s wrong in my query?

Thank you

11

the fact that you’re trying to sum datetimes

if this farce is to continue, i insist that you explain what it means to sum datetimes

12

I need to sum the times and minus in now().

so what query should I need?

Thanks

13

i think you need to step away from the computer for a day or so…