Time difference problem

$a =2014-09-30 23:21:55
$b =18:00

How can I figure out how many minutes the difference between 23:21 and $b is in $ A?

Reply to discussion (solution)

I got it!!!

$d = new DateTime (Date (' H:i:s ', Strtotime (' 2014-09-30 23:21:55 ')), $t = $d->diff (new datetime (' 18:00:0 ')); Echo $t- >format ('%h:%i:%s  '), echo $t->h * + $t->i + $t->s/60;

05:21:55 321.91666666667

$seconds = (Strtotime ("2014-09-30 23:21:55")-strtotime ("18:00") +86400)%86400; $minutes = Floor ($seconds/60); var_dump ($minutes);

Reference function: Strtotime

Or Baidu ' Calculate time difference '

If:
The value of Kq.kq_time is 2014-09-30 23:21:55
The value of kq_c.am_on is 18:00

How to make the following MySQL statement set up?
$sql _where. = "and Date_format (Kq.kq_time, '%h:%i ') >kq_c.am_on";

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