How to round unix timestamp up and down to nearest half hour?

php datetime unix-timestamp
Ash picture Ash · Mar 9, 2012 · Viewed 35.3k times · Source

Ok so I am working on a calendar application within my CRM system and I need to find the upper and lower bounds of the half an hour surrorunding the timestamp at which somebody entered an event in the calendar in order to run some SQL on the DB to determine if they already have something booked in within that timeslot.

For example I have the timestamp of 1330518155 = 29 February 2012 16:22:35 GMT+4 so I need to get 1330516800 and 1330518600 which equal 16:00 and 16:30.

If anyone has any ideas or think I am approaching developing the calendar in a stupid way let me know! Its my first time on such a task involving so much work with times and dates so any advice appreciated!

Answer

SenorAmor picture SenorAmor · Mar 9, 2012

Use modulo.

$prev = 1330518155 - (1330518155 % 1800);
$next = $prev + 1800;

The modulo operator gives the remainder part of division.

Related questions

Check whether the string is a unix timestamp

I have a string and I need to find out whether it is a unix timestamp or not, how can I do that effectively? I found this thread via Google, but it doesn't come up with a very solid answer, …

Read More
PHP-MYSQL: Converting Unix Timestamp to DateTime and vice versa

im using php 5.4.6 and MySQL 5.5.29 and I get trouble by converting a UNIX TIMESTAMP to MYSQL DATETIME and vice versa. Mysql and php wun on the same local machine. I have a simple mysql table CREATE TABLE Entry( id SERIAL …

Read More
MySQL: What's the best to use, Unix TimeStamp Or DATETIME

Probably many coders want to ask this question. it is What's the adventages of each one of those MySQL time formats. and which one you will prefer to use it in your apps. For me i use Unix timestamp because …

Read More