How to add 4 hours to time in PHP/MySQL

I'm working on a blog migration from a custom built blog to Wordpress. One of the fields that Wordpress is looking for in the database is a date/time stamp set to GMT, which is 4 hours ahead of our time. So I basically need to take our date/time stamp (in YYYY-MM-DD HH:MM:SS format), and add four hours to it. I was looking at the MySQL command "ADDTIME", but I think that only works on selects, not on inserts.

I had worked up a script that exploded the date in to parts, and added 4 hours to the time, but the ensuing logic that would be required to check for when 4 hours pu开发者_C百科shes in to the next day/month/year seemed a little excessive.

date($format, strtotime("$date + 4 hours"));

There's nothing that prevents ADDTIME() from being used in an INSERT OR UPDATE, but DATE_ADD() is probably what will work best:

INSERT INTO table_name
SET my_datetime = DATE_ADD('2009-11-01 19:30:00', INTERVAL 4 HOURS),
...other insert columns here... ;

What about:

date( "Y-m-d H:i:s", strtotime( "2009-08-09 23:44:22" )+4*60*60 )

or even

date( "Y-m-d H:i:s", strtotime( "2009-08-09 23:44:22 + 4 hours" ) )

Might need a bit of error checking, but should solve your problem.

Or better in SQL

DATE(DATE_ADD(`Table`.`Column`, INTERVAL 4 HOURS))

For all the answers using DATE_ADD, the correct syntax is "4 HOUR" not "4 HOURS" (at least in the current version of MySQL):

UPDATE table SET field = DATE_ADD(field, INTERVAL 4 HOUR);

It looks like the TZ of your database is set to GMT (UTC), which is as it should be. You need to convert your local date into GMT when adding to the database.

from the MySQL 5.1 Reference Manual:

CONVERT_TZ(dt,from_tz,to_tz)

CONVERT_TZ() converts a datetime value dt from time zone given by from_tz to the time zone given by to_tz and returns the resulting value. Time zones may be specified as described in Section 5.10.8, “MySQL Server Time Zone Support”. This function returns NULL if the arguments are invalid.

If the value falls out of the supported range of the TIMESTAMP type when converted fom from_tz to UTC, no conversion occurs. The TIMESTAMP range is described in Section 11.1.2, “Overview of Date and Time Types”.

mysql> SELECT CONVERT_TZ('2004-01-01 12:00:00','GMT','MET');
        -> '2004-01-01 13:00:00'

mysql> SELECT CONVERT_TZ('2004-01-01 12:00:00','+00:00','+10:00');
        -> '2004-01-01 22:00:00'

If you use (day/month/year)[Brazilian date format] as below, it doesn't work:

$todays_date = date("d/m/Y H:i:s");

echo "Server date/hour ". $todays_date;

echo "Server date/hour + 2 hours ".date("d/m/Y H:i:s", strtotime("$todays_date + 2 hours"));

Result:

Server date/hour                   10/04/2012 07:44:36

Server date/hour + 2 hours    04/10/2012 09:44:36

You need to you (month/day/year) and it works perfect:

$todays_date = date("m/d/Y H:i:s"); echo "Server date/hour ".

$todays_date."
"; echo ""Server date/hour + 2 hours ".date("m/d/Y H:i:s", strtotime("$todays_date + 2 hours"));

Result:

Server date/hour                    04/10/2012 07:44:36

Server date/hour + 2 hours    04/10/2012 09:44:36

I have used this method:

$format = Y-m-d; //you can use any format if you want
$date = $row['date']; // from mysql_fetch_array
$date2 = date($format, strtotime("$date + 4 week"));
echo $date;

Working 100%

<?php

$datee= date("Y-m-d", strtotime("$last_update+ 10 hours"));
$timee= date("H:i:s", strtotime("$last_update+ 10 hours"));
?>

Last update was on: <?php  echo $datee; ?>  at  <?php  echo $timee; ?>

$last_update is a value contents timestamp from mysql

The result will be like this "Last update was on: 2015-02-05 at 05:01:43"

<?php

function data_time($DT, $pm, $val, $time_type){
    $time = date("H:i:s");
    $date = date("d.m.Y");

    if($DT=='d'){
        switch($pm){
            case '+': $newData = date("d.m.Y ", strtotime("$date + $val $time_type"));
            break;
            case '-': $newData = date("d.m.Y ", strtotime("$date - $val $time_type"));
            break;
        }
        return $newData;
    }
    if($DT=='t'){
        switch($pm){
            case '+': $newTime = date("H:i:s ", strtotime("$time + $val $time_type"));
            break;
            case '-': $newTime = date("H:i:s ", strtotime("$time - $val $time_type"));
            break;
        }
        return $newTime;
    }
}

$newData = data_time('t','+',5,'year')
//or

$DataTime = 'd'; // 't' or 'd'
$PlusMinus ='+'; // '+' or '-'
$val = 1;        // 0-9
$DMT ='month';   // 'day', 'month' or 'year'

$newData = data_time($DataTime, $PlusMinus, $val, $DMT);
echo $newData;

?>

UPDATE table SET field = DATE_ADD(field, INTERVAL 4 HOURS);

Hence it is useful in php for adding fucntion to column