PHP merges two arrays on the same key value AND

I have two arrays. And I want to merge them on the same key AND value. If they have the same ur_user_id then they are merged. array2 only provides some additional data for array1, so the new_array.length = array1.length. array1 just gets the additional data from array2.

$array1 =
    array(
        array('ur_user_id'=> 1,'ur_fname'=>'PerA','ur_lname'=>'SonA'),
        array('ur_user_id'=> 2,'ur_fname'=>'PerB','ur_lname'=>'SonB'),
        array('ur_user_id'=> 3,'ur_fname'=>'PerC','ur_lname'=>'SonC'),
    );
$array2 =
    array(
        array('ur_user_id' => 5,'ur_code' => 'EE','ur_user_role' => 'testE'),
        array('ur_user_id' => 4,'ur_code' => 'DD','ur_user_role' => 'testD'),
        array('ur_user_id' => 6,'ur_code' => 'FF','ur_user_role' => 'testF'),
        array('ur_user_id' => 3,'ur_code' => 'CC','ur_user_role' => 'testC'),
        array('ur_user_id' => 1,'ur_code' => 'AA','ur_user_role' => 'testA'),
        array('ur_user_id' => 2,'ur_code' => 'BB','ur_user_role' => 'testB'),
    );

Then the new array must look like this. It will have both the values from the array1and array2.

$new_array =
    array(
        array('ur_user_id'=> 1,'ur_fname'=>'PerA','ur_lname'=>'SonA','ur_code' => 'AA','ur_user_role' => 'testA'),
        array('ur_user_id'=> 2,'ur_fname'=>'PerB','ur_lname'=>'SonB','ur_code' => 'BB','ur_user_role' => 'testB'),
        array('ur_user_id'=> 3,'ur_fname'=>'PerC','ur_lname'=>'SonC','ur_code' => 'CC','ur_user_role' => 'testC'),
    );

The array1.length is always less than or equal to array2.length never greater. And the order of both arrays will not be always ordered. I've tried the function below which I got somewhere here but it doesn't work for me and I'm not really good with loops.

function merge_common_keys(){
    $arr = func_get_args();
    $num = func_num_args();

    $keys = array();
    $i = 0;
    for ($i=0; $i<$num; ++$i){
        $keys = array_merge($keys, array_keys($arr[$i]));
    }
    $keys = array_unique($keys);

    $merged = array();

    foreach ($keys as $key){
        $merged[$key] = array();
        for($i=0; $i<$num; ++$i){
            $merged[$key][] = isset($arr[$i][$key]) ? $arr[$i][$key] : null;
        }
    }
    return $merged;
}

Based on the given arrays the result is like this. It only merges on the same key.

Array
(
    [0] => Array
        (
            [0] => Array
                (
                    [ur_user_id] => 1
                    [ur_fname] => PerA
                    [ur_lname] => SonA
                )

            [1] => Array
                (
                    [ur_user_id] => 5
                    [ur_code] => AA-BB-CC
                    [ur_user_role] => testE
                )

        )

---

Try out this code, It might help you, it's short and without traversing loops:

    usort($array2,function($a,$b){
        return strnatcmp($a['ur_user_id'],$b['ur_user_id']);
    });
    $array3 = array_replace_recursive($array1, $array2);

    $result = array_uintersect($array3,$array1,function($a,$b){
        return strnatcmp($a['ur_user_id'],$b['ur_user_id']);
    });
    print_r($result);

Output

Array
(
    [0] => Array
        (
            [ur_user_id] => 1
            [ur_fname] => PerA
            [ur_lname] => SonA
            [ur_code] => AA
            [ur_user_role] => testA
        )

    [1] => Array
        (
            [ur_user_id] => 2
            [ur_fname] => PerB
            [ur_lname] => SonB
            [ur_code] => BB
            [ur_user_role] => testB
        )

    [2] => Array
        (
            [ur_user_id] => 3
            [ur_fname] => PerC
            [ur_lname] => SonC
            [ur_code] => CC
            [ur_user_role] => testC
        )

)

strnatcmp in PHP

 PHP strnatcmp() function is utilized to analyze two strings using a "natural" algorithm.
The function returns :

0 – if the two strings are exactly equivalent.
<0 – if smaller byte is found in the string1.
>0 – if smaller byte is found in the string2.
Syntax:

strnatcmp(string1,string2)
string1 : Required. Specifies the first string

string2 : Required. Specifies the second string

Tip: This function is case-sensitive.

Example:

<?php
echo strnatcmp("4Good Morning","12Good Morning");
echo "<br />";
echo strnatcmp("12Good Morning","4Good Morning");
?>
Output will be:
-1
1