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<?php $array = Array ( 0 => array( 'Product' => array('id' => 21) ), 1 => array( 'Product' => array( 'id' => 43, 'children' => array( 0 => array( 'Product' => array('id' => 123) ), 1 => array( 'Product' => array('id' => 4323) ), 2 => array( 'Product' => array('id' => 3423) ) ) ) ), 2 => array( 'Product' => array('id' => 534) ) ); $keys = array_keys(array_column($array, 'id'), 1); $new_array = array_map(function($k) use ($array){return $array[$k];}, $keys); print_r($new_array);

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