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<?php $arr1 = Array( 0 => Array ( "day" => "17-3-2018" ), 1 => Array ( "day" => "16-3-2018" ), 2 => Array ( "day" => "15-3-2018" ), 3 => Array ( "day" => "14-3-2018" ) ); $arr2 = Array ( 0 => array ( "day" => "15-3-2018", "count" => 2 ), 1 => array ( "day" => "17-3-2018", "count" => 1 ) ); $day= array_column($arr1, "day"); Foreach($arr2 as $val){ $find = array_search($val['day'], $day); If($find !== false) $arr1[$find]['count'] = $val['count']; } Var_dump($arr1);
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
array(4) { [0]=> array(2) { ["day"]=> string(9) "17-3-2018" ["count"]=> int(1) } [1]=> array(1) { ["day"]=> string(9) "16-3-2018" } [2]=> array(2) { ["day"]=> string(9) "15-3-2018" ["count"]=> int(2) } [3]=> array(1) { ["day"]=> string(9) "14-3-2018" } }

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