Confused about the date/time processing logic

Question

Hi Experts,
i've sent this issue to OSS but they replied this is not a bug and not giving me any info, so I'm here ask for help:
(i've got 2 screenshots but it seems there's no upload in the sdn forum?)
we have the equipment warranty master data (check 1.jpg, the Warranties
assignment block)
and there're "Warranty Start" and "Warranty End" dates
we are confused how the data is saved and loaded with the timezones:
(how are the User Timezone & Server Timezone, or any other value related
in the following problems)
1, there're two pairs of columns, the 1st pair only shows date, the 2nd
pair shows the time also. --What's the diffenence?
2, when creating a new warranty master data, the 2nd pair shows the
hour/min/sec(in 1.jpg, "17:00:00"), by what logic, does the hour/min/sec
value come?
(in the 2.jpg, we can see different data with different hour stamps,
how is the value determined?)
3, how about if we use program to write the data, if we put timestamp
20120228000000 in the database, what does that mean to the system(which
timezone means to the system)?
4, when showing the start/end date data, by what logic (using which
timezone value) does the system calculated and then bring to the webUI ? (e.g. at Account Identification, after entered Serial Number in Objects, there're Warranty Start/End date, how's the value calculated?)
Thanks
Kane Xu

Answer 1

Hi All,
Thanks for your deatiled reply, I think the logic is somehow clear for me,
but now I'm facing a strange problem:
as the screenshot shows, the 2nd pair of time(with hour/min/sec) is the UTC time
I found that is stored in table COMM_IL_IOBWTY, the value is exactly the same on UI
we have a program and a FM, both using "  CALL FUNCTION 'CRM_IBCWTY_IL_API_CREATE' " staement to write this value.
the program is set as a background job, but for now, at testing period, we run it manually in se38 each time we need
the FM is called from EN_ONSAVE of an OVView page of webUI
in the code, both in the program and in the FM, we put 000000 for hr/min/sec,
they works fine in our dev system, but in qas system,
the FM works fine, and after running the program, the hour value in table(and in webUI) is not zero,it seems changing by user timezone settings.
I'm so confused and tried to debug into the 'CRM_IBCWTY_IL_API_CREATE' and not found any code might be related to timezone.
Do you have any idea why this happens? Thank you!
Kane