Check if a DATE and TIME has passed 3 days

Question

I have a string with a date and time in the format 2013-07-01 19:10:05 (Ymd H:i:s) . When I output data from a database where the date and time is stored, I want to see if three days have gone since that date and time .

Example: Stored in database is 2013-07-01 00:00:00 . 3 days after that stored date and time would be 2013-07-03 00:00:00 .

If that would be true, I want to echo some text.

I tried with the following but I think I am totally out sailing.

if( strtotime('-3 days') < strtotime($row["orderdatetime"]) ) {
   echo " <img src='imgs/warning.png' ></td >";
}

Thankful for any kind of help!

Sincerely, Andreas

EDIT:

This is how my PHP script looks like.

if ($row["confirmeddatetime"] == "0000-00-00 00:00:00" ) {
        $db_datetime = new DateTime($row['orderdatetime']);
        $db_plus_three = $db_datetime->add(new DateInterval('P3D'));
        $now_datetime = new DateTime();
        if ($db_plus_three < $now_datetime) {
            echo " <img src='imgs/warning.png' ></td >";
        } else {
            echo "</td >";
        }

Can anyone of you identify if something is wrong?

Answer 1

I would recommend using DateTime and DateInterval classes.

$db_datetime = new DateTime($row['orderdatetime']);
$db_plus_three = $db_datetime->add(new DateInterval('P3D'));
$now_datetime = new DateTime();

if ($db_plus_three < $now_datetime) {
   // this is more than 3 days old
}

An alternate approach would be to set a flag in the DB query itself like this:

SELECT
    [YOUR CURRENT FIELDS HERE],
    (CASE WHEN NOW() > DATE_ADD(orderdatetime, INTERVAL 3 DAYS) THEN 1 ELSE 0) AS three_days_old
    [REST OF QUERY HERE]

You could then easily identify by looking at three_days_old value whether the item was more than 3 days old.

Answer 2

Possibly the easiest way is to get the unix time directly from the database (assuming mysql):

SELECT *, UNIX_TIMESTAMP(orderdatetime) AS ordertimestamp...

then in your comparison you just need

if( strtotime('-3 days') < $row["ordertimestamp"] ) {
   echo " <img src='imgs/warning.png' ></td >";
}

Answer 3

strtotime converts a time string to a timestamp which is just an integer number of seconds. Just compare to time minus 3 * 86400 (seconds in a day)

Answer 4

SELECT (orderdatetime <= NOW() + INTERVAL 3 DAY) AS threedays ...

you'll get a 1/0 true/false value if 3 days have gone by or not. I suggest not doing such a comparison in PHP, as you'll be forcing a mysql date -> string -> int -> date conversion chain, wasting a lot of CPU cycles when you could just do the comparison directly in mysql.

Answer 5

Actually your second example works for me, just be careful with the add() function, it updates the value itself. This is a similar example how i use it myself:

/**
 * Checks if the elapsed time between $startDate and now, is bigger
 * than a given period. This is useful to check an expiry-date.
 * @param DateTime $startDate The moment the time measurement begins.
 * @param DateInterval $validFor The period, the action/token may be used.
 * @return bool Returns true if the action/token expired, otherwise false.
 */
function isExpired(DateTime $startDate, DateInterval $validFor)
{
  $now = new DateTime();

  $expiryDate = clone $startDate;
  $expiryDate->add($validFor);

  return $now > $expiryDate;
}

// how to use it
$startDate = new DateTime('2013-06-16 12:36:34');
$validFor = new DateInterval('P3D'); // valid for 3 days
$isExpired = isExpired($startDate, $validFor);