数据库中的时间倒计时[关闭]

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            <div class="grid--cell mb0 mt8">Closed <span title="2013-02-28 02:40:42Z" class="relativetime">7 years ago</span>.</div>
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I'm doing a simple auctioning site for a school project and I want to display a countdown for how long the auction will be active, starting from when its made and counting down a week or so (not set yet). I was thinking of when creating the auction, info is added into a database (what object, price, name, and time remaining). I would add what date and time the object is created and exactly 7 days after its no longer active. If I have time and date in my mySQL database, how would I display with php (or maybe AJAX? Never used it) the time remaining?

Any input is helpful as I'm completely stumped.

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