数组格式和排序

Question

It's 3am here, i'm super tired and I have no idea how to make this thing to work. The following array is returned from database and contains info like page views, date and messages for the last 7 days:

Array
(
  [0] => Array
    (
        [vws] => 9
        [mss] => 0
        [dt] => 2016-06-27
    )

  [1] => Array
    (
        [vws] => 4
        [mss] => 0
        [dt] => 2016-06-26
    )

  [2] => Array
    (
        [vws] => 1
        [mss] => 0
        [dt] => 2016-06-24
    )

  [3] => Array
    (
        [vws] => 7
        [mss] => 0
        [dt] => 2016-06-23
    )

)

This array should contain data even if there are no page views or messaged so this is what i'm looking for:

Array
(
  [0] => Array
    (
        [vws] => 0
        [mss] => 0
        [dt] => 2016-06-22
    )

  [1] => Array
    (
        [vws] => 13
        [mss] => 1
        [dt] => 2016-06-23
    )

  [2] => Array
    (
        [vws] => 7
        [mss] => 3
        [dt] => 2016-06-24
    )

  [3] => Array
    (
        [vws] => 45
        [mss] => 10
        [dt] => 2016-06-25
    )

  [4] => Array
    (
        [vws] => 0
        [mss] => 0
        [dt] => 2016-06-26
    )

  [5] => Array
    (
        [vws] => 0
        [mss] => 0
        [dt] => 2016-06-27
    )

  [6] => Array
    (
        [vws] => 5
        [mss] => 1
        [dt] => 2016-06-28
    )

)

Sorry if I was not clear enough. I will update my question if you need more info. Thank you in advance

EDIT It seems that using dt value as a key is a good idea but I still think that the same result could be achieved more easily by checking dt value with in_array.

Thanks to @ArtisiticPhoenix , this code works just fine for now:

    $new = [];
    foreach ($data as $k => $v) {
        $new[$v['dt']] = $v;
    }

    $Date = new DateTime();
    $days = [];
    for ($i = 0; $i < 7; ++$i) {
        $days[$Date->format('Y-m-d')] = [
            'vws' => 0,
            'mss' => 0,
            'dt'  => $Date->format('Y-m-d')
        ];
        $Date->modify('-1 days');
    }
    $final = array_merge($days, $new);

Answer 1

First build an array of each day with empty values

 //current date
$Date = new DateTime();

$days = array();
 //loop 7 times, seven days in the week  ( forget if it should be <= ) 7s to high for me to count in my head right now. :)~
for($i = 0; $i<7; ++$i ){
    $days[$Date->format('Y-m-d')] = array(
        'vws' => 0,
        'mss' => 0,
        'dt' => $Date->format('Y-m-d')  
    );
    //subtract 1 day from today's date.
    $DateTime->modify('-1 days');
}

Next, use array_merge to merge that with the db data

 $data = array_merge( $days, $dbDays );

Note the keys in the prepared array is the date. You'll want to add that to the db populated data as well, this makes array_merge replace those values instead of appending the entries on ( like it would do if they where just numbered indexes ). In any case it makes correlating the data so much easier

Alternatively you could add them in in the while loop from the db, like this

while( false !== ( $row = $stmt->fetch() ) ){
    $days[$row['dt']] = $row;
}

But I am not sure where the data comes from ( mysql_ mysqli_ PDO )