The array_column() function in php returns the values from a single column in the input array.

1. Code:

<?php
function getValuesColumnInArray($array, $columnName){
	$values = array_column($array, $columnName);
    return $values;
} 
  $a = array(
    array(
        'id' => 5698,
        'first_name' => 'Chocolate',
        'last_name' => 'kitkat',
    ),
    array(
        'id' => 4767,
        'first_name' => 'Bike',
        'last_name' => 'Activa',
    ),
    array(
        'id' => 3809,
        'first_name' => 'Mobile',
        'last_name' => 'Oppo',
    )
);
$values = getValuesColumnInArray($a, 'last_name');
print_r($values);
?>

2. Example:

Input:

$array = array(
    array(
        'id' => 5698,
        'first_name' => 'Chocolate',
        'last_name' => 'kitkat',
    ),
    array(
        'id' => 4767,
        'first_name' => 'Bike',
        'last_name' => 'Activa',
    ),
    array(
        'id' => 3809,
        'first_name' => 'Mobile',
        'last_name' => 'Oppo',
    )
);
column name = last_name

Output:

Array ( [0] => kitkat [1] => Activa [2] => Oppo )