How to convert the 24-hour hourly billing to the am/pm format

How do I convert the 24-hour hourly billing to the am/pm format? Date & nbsp; 24-hour time calculation & nbsp; & n how to convert the 24-hour time calculation to the am/pm format?
Date: 24-hour hourly date: am/pm
00:00:00?
00:00:01?
00:59:59?
01:00:00?
01:00:01?
11:59:59?
12:00:00?
12:00:01?
12:59:59?
13:00:00?
13:00:01?
23:00:00?
23:00:01?
23:59:59?

No general functions or anything?

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The remainder of the hour.
Modulo 0 is am modulo 1 is pm

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JS or PHP?

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Mind using unix Timestamps
Date ('A', time () using the date function ())
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Slow down, huh, huh

Ls correct

Echo date ('Y-m-d H: I: s A', strtotime ('2017-08-02 00:00:00 '));

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UPDATE table
SET 24-hour timing = IF (LEFT (24-hour timing, 2)> 12,
CONCAT (LEFT (24-hour hourly, 2)-12, RIGHT (24-hour hourly, 6 )),
24-hour timing ),
T = IF (LEFT (24-hour timing system, 2)> 12, 'AM', 'PM ');