<?php
$records = [
0 => [
'first_name' => 'abc',
'last_name' => 'cba',
'age' => '1'
],
1 => [
'first_name' => 'def',
'last_name' => 'fed',
'age' => '2'
],
2 => [
'first_name' => 'ghi',
'last_name' => 'ihg',
'age' => '3'
]
];
// Using the $records array from Example #1
//$firstNames = array_column($records, 'first_name', 'first_name');
$firstNames = array_column($records, 'first_name');
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