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<?php $results = array ( 0 => array ( 'id' => 1, 'name' => 'a', 'country' => 'x' ), 1 => array ( 'id' => 2, 'name' => 'b', 'country' => 'y' ) ); array_unshift($results, array_combine(array_keys($results[0]), array_keys($results[0]))); print_r($results);
Output for 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
Array ( [0] => Array ( [id] => id [name] => name [country] => country ) [1] => Array ( [id] => 1 [name] => a [country] => x ) [2] => Array ( [id] => 2 [name] => b [country] => y ) )

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