I've been working on facebook application. But I've faced with strange bug(?).
It I'm trying to get detailed info about any event using graph api start_date differs from the one if I'm trying to get it using fql. for example:
https://graph.facebook.com/209798352393506/ - start date is 2011-05-26T19:00:00
https://api.facebook.com/method/fql.query?query=select%20eid%2C%20name%2C%20tagline%2C%20pic%2C%20host%20%2C%20start_time%20from%20event%20where%20eid%20%3D209798352393506 - start time is 1306461600. Which in human readable format equals to Fri, 27 May 2011 02:00:00 GMT.
As you can see difference between got dates is 5 hours. Somtimes I'm getting dates which differ for 8 hours, sometimes - 6.
Correct date is the first one:
http://www.facebook.com/events/209798352393506/
I can't figure out what happens. All events I'm trying to view are from Denmark. My timezone is Europe/Kiev. Difference is 1 hour.
Is this a facebook's bug? Or documented feature? Or am I doing something wrong?
Link to the documentation or another answer in stackoverflow would be enough.
Here is two events
http://www.facebook.com/events/290600150977115/ - starts on 2012-03-22 at 20:00
http://www.facebook.com/events/289501924395338/ - starts on 2012-03-03 at 21:00
But. Using FQL I'm getting that first event starts on 2012-03-23 at 04:00. Difference is 8 hours. And the second one starts on 2012-03-04 at 06:00. In this case difference is 9 hours. Why???
It was because of daylight saving time.
Time difference between me and facebook(Los Angeles) sometimes was 8 sometimes 9 hours, because there was a moment when Denmakr alredy changed their time to summer time and los angeles - not.
The problem occured when event started "in winter time" and finished in summer time. In this case I needed to add one hour.
Facebook is weird.
From /fql/insights/
The end of the period during which the metrics were collected, expressed as a unix time (which should always be midnight, Pacific Daylight Time) or using the function end_time_date() which takes a date string in 'YYYY-MM-DD' format.
2011-05-26T19:00:00 ===> 2011-05-26T19:00:00 PDT ===> Fri, 27 May 2011 02:00:00 GMT.
Related
I'm creating a customized function that does some calculations for a given time.
When a time is entered in a cell, for example 4:00 PM, this is automatically converted into a date, in this case 12/30/1899 16:00:00 and when the function getTheMinutes() is called, it returns 2 instead of 0.
function getTheMinutes(dateTime){
return dateTime.getMinutes();
}
The behavior of the function is different if it's used for a most recent date like 5/1/2019 16:00:00.
I want the user to be able to just write a time in a cell then use the customized function in another cell. Please let me know your thoughts.
Now that you have indicated the time zone for your spreadsheet I can confirm what #RobG deduced almost a day ago, which is that Guatemala adjusted its difference relative to UTC. Something you have confirmed is treated as by two minutes with effect from October 5, 1918.
More specifically, the adjustment was of 2 minutes and 4 seconds and effective from 03:00 that day:
(Source IANA Version 2019b file northamerica.)
There have been very many such minor adjustments around the world over the years (even between towns in the same country) and adjustments continue, though usually of a whole hour – between 'standard' and Summer time. Sheets has very properly recognised that "normal arithmetic" 'does not work' across such a transition and while noon yesterday to noon today for example is normally, for any one specific location, a difference of 24 hours it is often 23 hours or 25 hours on the day that clocks go forward/back.
And the moral of the story is to beware of obliging Sheets to assume, for want of a specific date, that is has the index number 0 - i.e. is December 30, 1899.
I made some testing, and I found out that the formula is giving a wrong result any minute before 10/5/1918 0:03:00, from that DateTime on, the formula is working as expected.
Here is my sheet https://docs.google.com/spreadsheets/d/1psm8_GJYRczO53TILJCOzo0p4GpnS-ooiGWqOJrC8ZU/edit?usp=sharing
I would need to do a date validation in my customized formula to make it useful. I don't know why google sheets is choosing that date as default when just a time is typed in a cell, I think it should be improved.
I am working with an API that generates time periods based on a configured set of parameters.
So for example, I can specify I want 12 one month periods starting Jan 1st at midnight, and therefore the API will generate 12 monthly periods
01 Jan 2016 00:00:00 – 31 Jan 2016 23:59:59
01 Feb 2016 00:00:00 – 28 Feb 2016 23:59:59
Through to
01 Dec 2016 00:00:00 – 31 Dec 2016 23:59:59
Now the API expects a start date param supplied for the sequence of periods to be an ISO formatted string in UTC. So I’m currently in the UK, therefore if I choose to start the monthly periods from Jan 1st 2016 this would be 2016-01-01T00:00:00Z and is what I supply to the API call I am making to say when the first instance of my monthly periods should begin.
So now if I view the start and end dates of the generated monthly periods via the API, I will see them come back as
2016-01-01T00:00:00Z - 2016-01-31T23:59:59Z
2016-02-01T00:00:00Z - 2016-02-28T23:59:59Z
Etc to
2016-12-01T00:00:00Z - 2016-12-31T23:59:59Z
Something struck me about these generated periods and that is I want them to begin at midnight for where I currently am, but a period that is affected by GMT Daylight Time, so say my April period will look like so in the generated period from the API
2016-04-01T00:00:00Z - 2016-04-30T23:59:59Z
Parsing the start date for the above into a date object for viewing in the client (on my machine) will show up as
Fri Apr 01 2016 01:00:00 GMT+0100 (GMT Daylight Time)
So it’s saying that period starts at 1am and not midnight.
Now say if I wanted 12 months to be generated from 1st Jun when Daylight Savings is in effect.
My client side code currently will supply a start date to the API of 2016-05-31T23:00:00Z. This causes the API to generate start dates for each monthly period as being
2016-05-31T23:00:00Z - 2016-06-31T22:59:59Z (June Period)
2016-06-31T23:00:00Z - 2016-07-31T22:59:59Z (July)
Etc to
2017-04-30T23:00:00Z - 2017-05-31T22:59:59Z (May)
But now for a period that is not in GMT Daylight Time, so Jan for example it will show up as
2016-12-31T23:00:00Z - 2017-01-31T22:59:59Z
Meaning my client will see that start date as
Sat Dec 31 2016 23:00:00 GMT+0000 (GMT Standard Time)
So not Jan 1st at 00:00
Does this suggest that the API should know about the users timezone so the period generation logic in the API can factor this is when calculating the start and end dates?
Maybe I'm over thinking things here?!
The only real question I see here is:
Does this suggest that the API should know about the users timezone so the period generation logic in the API can factor this is when calculating the start and end dates?
In general, the answer is YES. Any time you are mapping calendar dates back to specific instants in time, then by definition you must involve time zones. That time zone can be that of the user's, or of some specific business location, or fixed to UTC, but they indeed part of the logic.
Consider that not every calendar date has a valid local "midnight" in every time zone. An example is 2015-10-18 in Sao Paulo Brazil, where the first moment of that day was 1:00 AM due to their spring-forward daylight saving time transition. There are many other examples of this around the world.
The only way to avoid the problem entirely is to not deal in specific times. If you are only working with whole dates, then your code can certainly compute the exact dates of each month without knowing anything about time zones. 2016-01-01 through 2016-01-31 has no awareness of time or time zone. It's only when you try to ask what the current date is, or if now is within that range, or if some other specific instant in time is within that range that you have to start thinking about time zones.
I have a field containing what should be a UNIX time stamp. As an example one value is 1408675380
Now when I do various online conversions, it shows the right day (22nd August) but shows the incorrect time. It should be around 21:00 or so but instead shows 02:43:00 GMT
Likewise, 1408676520 shows the correct day (22nd August) but instead of showing a time of around 22:00/23:00 it shows 03:02:00 GMT
I have no control over the data at all - just wondering if there's something obvious I'm missing?
1408849260 - Sunday, August 24th 2014, 03:01:00 (GMT) - Correct day, around 18 hours too early
1408850640 - Sunday, August 24th 2014, 03:24:00 (GMT) - Correct day, around 18 hours too early
Thanks,
JJ
Is your data in some other timezone than GMT ? something like GMT-5 (america west cost maybe ?)
I don't understand the way the API returns values. Here's a sample of a page_impressions call, with 'week' as the period.
"values"=>
[{"end_time"=>"2012-01-08T08:00:00+0000", "value"=>1116},
{"end_time"=>"2012-01-09T08:00:00+0000", "value"=>1171},
{"end_time"=>"2012-01-10T08:00:00+0000", "value"=>1175}]
It seems that they're showing how many hits I had in the last 7 days up to the date in "end_time", is that correct? If it is, then I don't understand what use this would have, there is a huge overlap in the data.
How can I get the number of impressions of the last weeks instead? And how can I get more than 3 values to display? I really can't understand the logic behind this or how it could be useful.
What's happening here is that you're being given the total number of page_impressions for the 7-day period ending on each of the dates shown (i.e., how many times was the page seen over the past 7 days assuming the week ended on the end_time? and then on end_time+1? end_time+2)
Facebook is returning three (3) separate readings, presumably so you can spot/review very local trends (e.g., "are my weekly impressions creeping up?) or perhaps because you missed a measurement and want to have values for every day.
To answer your question specifically:
The 7-day period 2012-01-01 through 2012-01-08 12:00am* had 1,116 impressions.
The 7-day period 2012-01-02 through 2012-01-09 12:00am* had 1,171 impressions.
The 7-day period 2012-01-03 through 2012-01-10 12:00am* had 1,175 impressions.
As is quoted below, the end_time itself is always midnight in PDT. Thus, an end_time of 2012-01-08 really means the measurement stopped the night before, i.e., at 1 minute past 11:59pm on 2012-01-07.
From https://developers.facebook.com/docs/reference/fql/insights/:
The end of the period during which the metrics were collected,
expressed as a UNIX time (which should always be midnight, Pacific
Daylight Time) or using the function end_time_date() which takes a
date string in 'YYYY-MM-DD' format. Note: If the UNIX time provided is
not midnight, Pacific Daylight Time, your query may return an empty
resultset. Example: To obtain data for the 24-hour period starting on
September 15th at 00:00 (i.e. 12:00 midnight) and ending on September
16th at 00:00 (i.e. 12:00 midnight), specify 1284620400 as the
end_time and 86400 as the period. Note: end_time should not be
specified when querying lifetime metrics.
What is the valid format for start_time and end_time while adding an event using graph api ...
i tried adding an event using unix time stamp .. however its not showing the same date when the event is published ..
when i give start_time as 1293802200 which is 31st Dec 2010 07:00 pm .. it shows as 31st Dec 5:30am on facebook ..
what is it that am doing wrong .. do i need to consider time zone issues as well ??
Regards
Abhishek Jain
According to http://developers.facebook.com/docs/reference/api/event/ it seems that you need to specify date in the Pacific time zone (PST).
Now, the timestamp value you provided is 31st Dec 2010 19:00 in India indeed which corresponds to same day, 5:30 in Pacific time.
In conclusion, convert your local time to Pacific time (PST) prior to uploading it to Facebook.