How to compare 2 multidimensional arrays and keep order?

Question

PHP

There are 2 arrays
$result2:

array(29) {
  [0]=>
  array(5) {
    ["users_id"]=>
    string(2) "19"
    ["date"]=>
    string(10) "2020-04-01"
    ["user_id"]=>
    string(2) "19"
    ["sub_hours"]=>
    string(1) "8"
  }
  [71]=>
  array(5) {
    ["users_id"]=>
    string(3) "108"
    ["date"]=>
    string(10) "2020-04-02"
    ["user_id"]=>
    string(3) "108"
    ["sub_hours"]=>
    string(1) "8"
  }
  [139]=>
  array(5) {
    ["users_id"]=>
    string(2) "91"
    ["date"]=>
    string(10) "2020-04-03"
    ["user_id"]=>
    string(2) "91"
    ["sub_hours"]=>
    string(1) "8"
  }

and
$result_days:

array(202) {
  [0]=>
  array(3) {
    ["id"]=>
    string(3) "123"
    ["off_date"]=>
    string(10) "2019-04-27"
    ["off_id"]=>
    string(1) "1"
  }
  [1]=>
  array(3) {
    ["id"]=>
    string(3) "118"
    ["off_date"]=>
    string(10) "2019-04-28"
    ["off_id"]=>
    string(1) "0"
  }
  [2]=>
  array(3) {
    ["id"]=>
    string(3) "111"
    ["off_date"]=>
    string(10) "2019-04-29"
    ["off_id"]=>
    string(1) "0"
  }
  [3]=>
  array(3) {
    ["id"]=>
    string(3) "112"
    ["off_date"]=>
    string(10) "2019-04-30"
    ["off_id"]=>
    string(1) "0"
  }
  [4]=>
  array(3) {
    ["id"]=>
    string(3) "119"
    ["off_date"]=>
    string(10) "2019-05-01"
    ["off_id"]=>
    string(1) "0"
  }
  [5]=>
  array(3) {
    ["id"]=>
    string(3) "120"
    ["off_date"]=>
    string(10) "2019-05-05"
    ["off_id"]=>
    string(1) "0"
  }

I am making a table in thead in which it is necessary to make a selection for the days that match in both arrays,
I try to do this

foreach ($result_days as $dateUsers) {
            foreach ($result2 as $i2) {
                if ($dateUsers['off_date'] === $i2['date']) {
                    echo "<td class='vihodnoy'>" . $i2['date'] . "</td>";
                } else {
                    echo "<td class='obichniyDen'>" . $i2['date'] . "</td>";
                }
            }
        }

$dateUsers['off_date'] === $i2['date'] - doesn't work and all days go to else , why is that?
The thing is that you need to save all the days in ascending order

Answer 1

It is not at all clear from the code what is being compared with what. If the arrays are in the $result_days and $result2 variables, then a cell will be displayed for each pair of elements (i.e. the total number of cells will be equal to the product of the array sizes). You probably didn't think about it.
On the main question: looking for something in a multidimensional array without indexes is unpleasant. Make the keys in the array you are comparing against, like so:

$result_days = [
  "2019-04-27" => [ "id" => "123", ... ],
  ...
];

foreach ($result2 as $i2) {
                if (array_key_exists($i2['date'], $result_days) {
...