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<?php $array = [ 'a' => [ 'name' => "Name 1", 'age' => "99", 'add' => "" ], 'b' => [ 'name' => "Name 2", 'age' => "99", 'add' => "Add2" ], 'c' => [ 'name' => "Name 3", 'age' => "99", 'add' => "Add3" ], 'd' => [ 'name' => "", 'age' => "", 'add' => "Add4" ] ]; $result = []; foreach ($array as $rowKey => $row) { foreach ($row as $key => $value) { if (!strlen($value)) { $result[$rowKey][] = $key; } } } var_export($result);

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