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<?php $arr = [ 1 => [ 'Date' => '2015-11-05' ], 2 => [ 'Date' => '2015-11-11' ] ]; uksort($arr,'mySortDate'); function mySortDate($a,$b) { $aDate = strtotime($a['Date']); $bDate = strtotime($b['Date']); if ($aDate == $bDate) { return 0; } return ($aDate < $bDate) ? -1 : 1; } print "<pre>"; var_dump($arr);

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