Date time comparisons

[Paul-D]

Hi I have 2 MySQL date times I want to subtract them and display the number of hours minutes and seconds (seconds optional) I could have days but would be happy if the hours were more than 24.

Thanks.

Paul.

 

[requinix]

There might be something useful here.

[Paul-D]

Thanks for these. These are useful functions but in my case I am extracting to date time values from different tables not in the same SQL so I think I need a PHP solution.

$a = "2018-08-26 12:20:00"

$b = "2018-08-27 13:30:05"

So $c would be either 1 day : 1 hour: 10 minutes: and 5 seconds OR 25 hours 10 minutes: 5 seconds.

Sorry not so strait forward.

[Paul-D]

Maybe turn them into a time stamp subtract them and just print out

 

$c = date('d H:i:s' ,$time);

[requinix]

Oh, you want to do this in PHP.

One big question here: what about DST? In the US it will end Nov 4. If you had two dates, Nov 3 12pm and Nov 4 12pm, would you want the result to be 24 hours (because that's what it looks like) or 25 hours (because that's the actual difference)?

[cyberRobot]

29 minutes ago, Paul-D said:

These are useful functions but in my case I am extracting to date time values from different tables not in the same SQL so I think I need a PHP solution.

That shouldn't matter. You could run a query to get the first date/time and assign the value to a PHP variable. In your second query you could execute the TIMEDIFF() function where one argument is the PHP variable created earlier. The other argument would be the other date/time.

[Barand]

Or consider using a join, so you have a single query on the two tables instead of two separate queries.

[maxxd]

If you're specifically looking for a PHP solution, DateTime::diff() sounds about perfect. You'll have your difference, but be able to format that difference in a variety of ways. Unless I'm not  understanding the issue.