在php中为数组添加缺少的日期索引

Question

I have the following array from a count query:

array = (
  0=>array(
    'date'=>2017-09-01,
    'total'=>4
  ),
  1=>array(
    'date'=>2017-09-03,
    'total'=>6
  ),
  # and so on..
);

I want to fill the date even if my query has no records on that date! How can I add the missing date index to the array. The dates are to be sequential. so I want the following output:

array = (
  0=>array(
    'date'=>2017-09-01,
    'total'=>4
  ),
  1=>array(
    'date'=>2017-09-02,
    'total'=>0
  )
  2=>array(
    'date'=>2017-09-03,
    'total'=>6
  ),

Answer 1

Extended solution with DateTime object, array_map and range functions:

$arr = [
        ['date' => '2017-09-01', 'total' => 4],
        ['date' => '2017-09-07', 'total' => 6],
        ['date' => '2017-09-09', 'total' => 7]
];

$result = [];
foreach ($arr as $k => $item) {
    $d = new DateTime($item['date']);
    $result[] = $item;
    if (isset($arr[$k+1])) {
        $diff = (new DateTime($arr[$k+1]['date']))->diff($d)->days;
        if ($diff > 1) {
            $result = array_merge($result , array_map(function($v) use($d){
                $d_copy = clone $d;
                return [
                    'date' => $d_copy->add(new DateInterval('P' . $v. 'D'))->format('Y-m-d'),
                    'total' => 0
                ];
            }, range(1, $diff-1)));
        }
    }
}

print_r($result);

The output:

Array
(
    [0] => Array
        (
            [date] => 2017-09-01
            [total] => 4
        )

    [1] => Array
        (
            [date] => 2017-09-02
            [total] => 0
        )

    [2] => Array
        (
            [date] => 2017-09-03
            [total] => 0
        )

    [3] => Array
        (
            [date] => 2017-09-04
            [total] => 0
        )

    [4] => Array
        (
            [date] => 2017-09-05
            [total] => 0
        )

    [5] => Array
        (
            [date] => 2017-09-06
            [total] => 0
        )

    [6] => Array
        (
            [date] => 2017-09-07
            [total] => 6
        )

    [7] => Array
        (
            [date] => 2017-09-08
            [total] => 0
        )

    [8] => Array
        (
            [date] => 2017-09-09
            [total] => 7
        )
)