<?php
$array = [
"date_2018_08" => 81,
"date_2018_09" => 70,
"date_2018_10" => 70,
"date_2018_11" => 95,
"date_2018_12" => 75,
"date_2019_01" => 91,
"date_2019_02" => 78,
"date_2019_03" => 95,
"date_2019_04" => 68,
];
$year = 2019;
$month = str_pad(4,2,"0",STR_PAD_LEFT);
$temp = array_filter($array, function ($key) use ($year, $month) {
return (strpos($key, $year . "_" . $month) === false);
}, ARRAY_FILTER_USE_KEY);
print_r($temp);die;
preferences:
61.63 ms | 402 KiB | 5 Q