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NOW() function in PHP


Question

Is there a PHP function that returns the date and time in the same format as the MySQL function NOW()?

I know how to do it using date(), but I am asking if there is a function only for this.

For example, to return:

2009-12-01 00:00:00
2019/07/13
1
492
7/13/2019 6:03:45 PM

Accepted Answer

Not besides the date function:

date("Y-m-d H:i:s");
2020/03/30
1049
3/30/2020 10:20:10 AM

date('Y-m-d H:i:s')

Look here for more details: http://pl.php.net/manual/en/function.date.php

2018/05/10

With PHP version >= 5.4 DateTime can do this:-

echo (new \DateTime())->format('Y-m-d H:i:s');

See it working.

2014/10/29

Use this function:

function getDatetimeNow() {
    $tz_object = new DateTimeZone('Brazil/East');
    //date_default_timezone_set('Brazil/East');

    $datetime = new DateTime();
    $datetime->setTimezone($tz_object);
    return $datetime->format('Y\-m\-d\ h:i:s');
}
2015/10/20

Short answer

$now = date_create()->format('Y-m-d H:i:s');

Read below for the long answer.




The mimicry of the MySQL NOW() function in PHP

Here is a list of ways in PHP that mimic the MySQL NOW() function.

// relative date
$now = date_create('now')->format('Y-m-d H:i:s'); // works in php 5.2 and higher  
$now = date_create()->format('Y-m-d H:i:s'); // also works in php 5.2
$now = new DateTime('now')->format('Y-m-d H:i:s'); // syntax error!!!
$now = (new DateTime('now'))->format('Y-m-d H:i:s'); // works in php 5.4 and higher   
$now = date('Y-m-d H:i:s'); // Slightly higher performance, but less usable for date/time manipulations

// From Unix timestamp
// Using date_create() with a Unix timestamp will give you a FALSE,  
// and if you try to invoke format() on a FALSE then you'll get a: 
//     Fatal error: Call to a member function format() on boolean 
// So if you work with Unix timestamps then you could use: date_create_from_format().
$unixTimeStamp = 1420070400; // 01/01/2015 00:00:00
$y2015 = date_create_from_format('U', $unixTimeStamp, timezone_open('Europe/Amsterdam'))->format('Y-m-d H:i:s');
$y2015 = date('Y-m-d H:i:s', $unixTimeStamp);

I think that date_create()->format('Y-m-d H:i:s') is the best way because this approach allows you to handle time/time-zone manipulations easier than date('Y-m-d H:i:s') and it works since php 5.2.


MySQL NOW() function

The MySQL function NOW() gives the dateTime value in this format: 'YYYY-MM-DD HH:MM:SS'. See here: https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_now.

An interesting fact is that it's possible to get the datetime format by running this query: SHOW VARIABLES LIKE 'd%e_format', the result could be something like this:

Variable_name     Value     
date_format       %Y-%m-%d
datetime_format   %Y-%m-%d %H:%i:%s

The variables up here are read-only variables. So you can't change it.

I guess the MySQL NOW() function gets it's format from the datetime_format variable.




The advantages of date_create()->format() instead date() summary

The favorable facts of date_create('now')->format('Y-m-d H:i:s') over date('Y-m-d H:i:s') are:

  • easier to handle time manipulations
  • easier to handle timezones
  • o.o.p.

The disadvantages of date_create()->format() instead date()

The function date() has a slightly better performance than date_create()->format(). See benchmark test below.

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $a = date_create('now')->format('Y-m-d H:i:s');
}
$end = time();                  
$elapsedTimeA = $end - $start;

echo 'Case A, elapsed time in seconds: ' . $elapsedTimeA;
echo '<br>';

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $b = date('Y-m-d H:i:s');
}
$end = time();                   
$elapsedTimeB = $end - $start;

echo 'Case B, elapsed time in seconds: ' . $elapsedTimeB;
echo '<br>';
// OUTPUT
Case A, elapsed time in seconds: 31
Case B, elapsed time in seconds: 14

The upper case shows that date() is faster. However, if we change the test scenario a bit, then outcome will be different. See below:

$start = time();
$dt = date_create('now');
for ($i = 0; $i <= 5000000; $i++) {
    $a = $dt->format('Y-m-d H:i:s');
}
$end = time();                  
$elapsedTimeA = $end - $start;

echo 'Case A, elapsed time in seconds: ' . $elapsedTimeA;
echo '<br>';

$start = time();
for ($i = 0; $i <= 5000000; $i++) {
    $b = date('Y-m-d H:i:s');
}
$end = time();                   
$elapsedTimeB = $end - $start;

echo 'Case B, elapsed time in seconds: ' . $elapsedTimeB;
echo '<br>';
// OUTPUT
Case A, elapsed time in seconds: 14
Case B, elapsed time in seconds: 15

The DateTime method: format() is faster here than date().




The advantages of date_create()->format() instead date() detailed

Read on for the detailed explanation.

easier to handle time manipulations

date_create() accepts a relative date/time format (like now, yesterday or +1 day) see this link, example:

$tomorrow = date_create('+1 day')->format('Y-m-d H:i:s'); 

date() accepts a relative date/time format as well, like this:

$tomorrow = date('Y-m-d H:i:s', strtotime('+1 day'));
$tomorrow = date('Y-m-d H:i:s', (time() + 86400)); // 86400 seconds = 1 day

easier to handle timezones

When timezones matter then the usage of date_create()->format() makes a lot more sense then date() because date() uses the default time zone which is configured in php.ini at the date.timezone directive. Link: http://php.net/manual/en/datetime.configuration.php#ini.date.timezone .

It is possible to change the timezone during run-time. Example:

date_default_timezone_set('Asia/Tokyo');.

The downside of that is that it will affect all date/time functions. This problem doesn't exists if you are using date_create()->format() in combination with timezone_open().

PHP supports major timezones. The funny thing is that it even supports the Arctic circle, and Antarctica. Have you ever heard about Longyearbyen? If not, then don't worry, neither did I until I read the official PHP documentation.

$nowLongyearbyen = date_create('now', timezone_open('Arctic/Longyearbyen'))->format('Y-m-d H:i:s');

See a list of all supported timezones: http://php.net/manual/en/timezones.php.

o.o.p.

O.O.P. uses state-full Objects. So I prefer to think in this way:

// Create a DateTime Object. 
// Use the DateTime that applies for tomorrow.
// Give me the datetime in format 'Y-m-d H:i:s'
$tomorrow = date_create('+1 day')->format('Y-m-d H:i:s'); 

Then to think in this way:

// Give me a date time string in format 'Y-m-d H:i:s', 
// use strtotime() to calculate the Unix timestamp that applies for tomorrow.
$tomorrow = date('Y-m-d H:i:s', strtotime('+1 day'));

Therefore I would say that the date_create()->format() approach is more readable to me then date().




date_create() VS new DateTime()

The favorable facts of date_create() over new DateTime() are:

  • Namespaces

Namespaces

If you work in a namespace and want to initialise a DateTime object with the new keyword, then you have to do it like this:

namespace my_namespace;

// The backslash must be used if you are in a namespace.
// Forgetting about the backslash results in a fatal error.
$dt = new \DateTime();

There is nothing wrong with this, but the downside of the above is that people forget sporadically about the backslash. By using the date_create() constructor function you don't have to worry about namespaces.

$dt = date_create(); // in or not in a namespace it works in both situations




Example of date_create()->format()

I use this approach for my projects if I have to fill an array. Like this:

$array = array(
    'name' => 'John',
    'date_time' => date_create('now')->format('Y-m-d H:i:s'), // uses the default timezone
    'date_time_japan' => date_create('now', timezone_open('Asia/Tokyo'))->format('Y-m-d H:i:s'),
);
2020/02/19

Try this:

date("Y-m-d H:i:s");
2018/05/10

Source: https://stackoverflow.com/questions/1995562
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