Dealing with Dates

Here's what I need to do:

开发者_C百科

1. I want to insert a date into a datetime MySQL field 30 days from from the current date
2. When I pull that specific record, I want to be able to check whether that date has passed yet or not (i.e. expiration date)

---

INSERT INTO the_table
   (fields, the_date_field)
VALUES
   (?, DATE_ADD(NOW(), INTERVAL 30 DAY))

---

SELECT
   the_date_field < NOW() AS expired
FROM
   the_table

Confirm:

SELECT '2010-01-01' < NOW() AS expired;
+---------+
| expired |
+---------+
|       1 |
+---------+

SELECT '2012-01-01' < NOW() AS expired;
+---------+
| expired |
+---------+
|       0 |
+---------+

---

For your insert:

$thirty_days_from_today = date('Y-m-d H:i:s', time() + 60*60*24*30);

Checking expiration dates:

if(strtotime($row['expiration_date']) < time()) {
    // expired
}

---

Strtotime is your friend on this one, both for ensuring that the input you're sending through data is "understandable" by PHP and also for doing math such as "+10 days" which would return the date ten days from today. It's really amazing what you can throw at strtotime.

Checking dates is as simple in a MySQL query or PHP comparison with an operator -- Like >, < <>, etc.

---

Since you're using PHP, you can utilize strtotime()

$date = date( 'Y-m-d', strtotime( '+30 days' ) );

strtotime can handle other increments (+1 days, +5 minutes, etc)

You can also use strtotime to compare the dates when you read them out of the database. If you're storing in full-day (no timestamp) format, you'll need to divide by a full day's worth of seconds.

$expdate = strtotime( date( 'Y-m-d', $record[ 'expiration_date' ] ) );
$today = strtotime( date( 'Y-m-d' ) );
$isExpired = round( abs( $expiration - $today ) / ( 24 * 60 * 60 ) ) >= 0;