PHP将具有相同键的数组合并到一个自定义数组

Question

I have multiple result from mysql in array like this

Array1

Array
(
  [type] => Food
  [storage] => S5213
  [quantity1] => 1000
  [in1] => 10/09/2017
  [quantity2] => 1000
  [in2] => 10/09/2017
)

Array 2

Array
(
  [type] => Food
  [storage] => S4512
  [quantity1] => 990
  [in1] => 13/09/2017

)

Array 3

Array
(
  [type] => Drink
  [storage] => K4221
  [quantity1] => 12000
  [in1] => 12/09/2017
)

So, i would like to merge if the key such as "type" from different arrays are same and put it into custom array. At the same time, it maybe has quantity1, quantity2, quantity3 and in1,in2,in3 for different stocks quantity and date. Would like to merge it into "rack".

Expected result

Array
(
[Food] => Array
    (
        [0] => Array
            (
                [storage] => S5213
                [rack] => Array
                    (
                        [0] => Array
                            (
                                [quantity] => 1000
                                [in] => 10/09/2017
                            )

                        [1] => Array
                            (
                                [quantity] => 1000
                                [in] => 10/09/2017
                            )

                    )

            )

        [1] => Array
            (
                [storage] => S4512
                [rack] => Array
                    (
                        [0] => Array
                            (
                                [quantity] => 990
                                [in] => 13/09/2017
                            )

                    )

            )

    )

[Drink] => Array
    (
        [0] => Array
            (
                [storage] => K4221
                [rack] => Array
                    (
                        [0] => Array
                            (
                                [quantity] => 12000
                                [in] => 12/09/2017
                            )

                    )

            )

    )

)

Is it possible? tried using array_merge_recursive, but not output expected result.

Answer 1

If this is what your SQL query returns, then it looks like your database is not normalised. More concretely, you should not have columns quantity1 , quantity2 , ...etc in a single table. The rule is, if you have more than one of some field, create a separate table. In this case that table should just have a foreign key, maybe a sequence number (1, 2, ...) and finally a single quantity column. Multiple quantities would be expressed as multiple rows in that additional table. The in field could be added to that, as it seems to follow the same rule.

Anyway, for the given situation, you could use this PHP function:

function addArray(&$main, $arr) {
    if (!is_array($main)) $main = []; // first time
    $main[$arr["type"]][] = [
        "storage" => $arr["storage"],
        "rack" => array_reduce(array_keys($arr), function ($acc, $key) use ($arr) {
            if (strpos($key, "quantity") === 0) {
                $acc[] = [
                    "quantity" => $arr[$key],
                    "in" => $arr[str_replace("quantity", "in", $key)]
                ];
            }
            return $acc;
        }, [])
    ];
}

Use it as follows:

$arr = [
  "type" => "Food",
  "storage" => "S5213",
  "quantity1" => 1000,
  "in1" => "10/09/2017",
  "quantity2" => 1000,
  "in2" => "10/09/2017"
];
addArray($main, $arr);

$arr = [
  "type" => "Food",
  "storage" => "S4512",
  "quantity1" => 990,
  "in1" => "13/09/2017"
];
addArray($main, $arr);

$arr = [
  "type" => "Drink",
  "storage" => "K4221",
  "quantity1" => 12000,
  "in1" => "12/09/2017"
];
addArray($main, $arr);

... etc. $main will have the desired structure.