我们如何使用php从数组中获取唯一数据的总和

I need to take sum of beds of unique date from array. I had tried with foreach but I am getting repeated data.

How can I get data like,

on 01.08.18 I have 3 bookings and sum of beds is 10

on 02.08.18 I have 3 bookings and sum of beds is 18

on 03.08.18 I have 2 bookings and sum of beds is 7

<?php
$dates = ['01.01.18', '02.01.18', '03.01.18']; //Dates are getting from daterange datepicker and preparing dates using php and stored in array. 
foreach($dates as $date) {
// fetching data from table where date is matching with "$date".
    $bookings = [
                 ['date' => '01.01.18', 'beds' => '2'],
                 ['date' => '01.01.18', 'beds' => '3'],
                 ['date' => '01.01.18', 'beds' => '5'],
                 ['date' => '02.01.18', 'beds' => '7'],
                 ['date' => '02.01.18', 'beds' => '6'],
                 ['date' => '02.01.18', 'beds' => '5'],
                 ['date' => '03.01.18', 'beds' => '2'],
                 ['date' => '03.01.18', 'beds' => '5'],
                ];

}
foreach($bookings as $booking) {
    print_r($booking['date']);
}

Checkout the live result here: https://3v4l.org/nHijY

$arr = array();

foreach($bookings as $booking) {
    $date = $booking['date'];

    if(array_key_exists($date, $arr))
        $arr[$date][] = $booking['beds'];
    else
        $arr[$date] = array($booking['beds']);
}

foreach($arr as $key => $value)
{
    $count = count($value);
    $sum = array_sum($value);

    echo "on {$key} I have {$count} bookings and sum of beds is {$sum}
";
}

You can use array_reduce to iterate over bookings array and for each booking update the sum if dates match:

Using array_reduce

Online Demo

$result = array_reduce( $bookings, function ($carry, $booking) use ($dates) {

    $date = $booking['date'];

    // Go to the next iteration if date doesn't exist
    if ( !in_array( $date, $dates ) ) {
        return $carry;
    }

    // Update sum if we have the same date Otherwise create new array
    if ( isset( $carry[ $date ] ) ) {
        $carry[$date]['sum'] += $booking['beds'];
        $carry[$date]['count']++;
    } else {
        $carry[ $date ] = [ 'sum' => $booking['beds'], 'count' => 1 ];
    }

    return $carry;

});

Using a simple foreach

Online Demo

$result = []; 

foreach($bookings as $booking) {

    $date = $booking['date'];

    // go to the next iteration if date doesn't exists
    if ( !in_array( $date, $dates ) ) {
        continue;
    }

    if ( isset( $result[ $date ] ) ) {
        $result[$date]['sum'] += $booking['beds'];
        $result[$date]['count']++;
    } else {
        $result[ $date ] = [ 'sum' => $booking['beds'], 'count' => 1 ];
    }

}