$q_all = "SELECT COUNT(*) AS q_otdels FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT (*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT (*) AS q_director FROM works WHERE rang = 1";

$quantity_all = mysql_fetch_assoc($quantity);
как я теперь могу вытащить первое значение по примеру 
$sum_d[0]
 теперь ведь у меня переменная будет $quantity_all['q_director'] 
а  она кажется не вытащит уже количества диреткоров...

   while ($quantity_all = mysql_fetch_assoc($quantity)) {
        echo $quantity_all["q_director"];
    } 

$quantity_all['q_director'] 

$q_all = "SELECT COUNT(*) AS q_otdels FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT (*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT (*) AS q_director FROM works WHERE rang = 1";

$num_dir = count($quantity_all);

  $q_all = "
  SELECT COUNT(*) AS q_otdels FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT (*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT (*) AS q_director FROM works WHERE rang = 1";

    $quantity_all = mysql_query($q_all);
    $quantity = mysql_fetch_assoc($quantity_all);

    $num = count($quantity['q_otdels']);
  
 echo "Статистика: всего отделов - ".$num.";

$quantity_all = mysql_query($q_all) or die("fail");

   $num = $quantity['q_otdels'];
  
 echo "Статистика: всего отделов - ".$num.";

print_r ($quantity);

$q_all = "SELECT COUNT(*) AS q_otdels FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT (*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT (*) AS q_director FROM works WHERE rang = 1";
				 $quantity_all = mysql_query($q_all) or die(mysql_error());
				 $quantity = mysql_fetch_assoc($quantity_all);

	 $q_all = "SELECT id FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT(*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT(*) AS q_director FROM works WHERE rang = 1";
				 $quantity_all = mysql_query($q_all) or die(mysql_error());
				 $quantity = mysql_fetch_assoc($quantity_all);
				
				
print_r ("massiv - ".$quantity['q_workers']);
echo "<br>massiv2 - ".count($quantity['q_workers']);
print_r ("<br>massiv3 - ".$quantity);

Notice: Undefined index: q_workers in C:\apache\localhost\www\mark\departments.php on line 88
 massiv - 
Notice: Undefined index: q_workers in C:\apache\localhost\www\mark\departments.php on line 89

massiv2 - 0
massiv3 - Array
Notice: Undefined variable: num in C:\apache\localhost\www\mark\departments.php on line 94

Notice: Undefined index: q_heads in C:\apache\localhost\www\mark\departments.php on line 94

Notice: Undefined index: q_workers in C:\apache\localhost\www\mark\departments.php on line 94

print_r ("<br>massiv4 - ".$quantity['q_workers']);
echo "<br>massiv5 - ".$quantity;

massiv4 - 
massiv5 - Array

print_r ("<br>massiv3 - ".$quantity);

print " \n massiv3 \n"; print_r($quantity); print " \n ";

print " \n massiv3 \n"; print_r($quantity); print " \n ";

massiv3 Array ( [id] => 1 )

SELECT id FROM otdel UNION
  SELECT COUNT(*) AS q_workers FROM works WHERE rang = 3 UNION
  SELECT COUNT(*) AS q_heads FROM works WHERE rang = 2 UNION
  SELECT COUNT(*) AS q_director FROM works WHERE rang = 1

SELECT `id` FROM `otdel` UNION SELECT COUNT(*) AS `q_workers` FROM `works` WHERE `rang` IN (3, 2, 1);

SELECT COUNT(*) AS `counts`, `rang` FROM `works` GROUP BY `rang`

$q = "SELECT id FROM otdel UNION
  SELECT id AS workers FROM works WHERE rang = 3 UNION
  SELECT id AS heads FROM works WHERE rang = 2 UNION
  SELECT id AS director FROM works WHERE rang = 1";

$quantity_all = mysql_query($q);

$quantity = mysql_fetch_assoc($quantity_all);

$sql1 = "SELECT COUNT(*) FROM works WHERE rang = 3";
$sql2 = "SELECT COUNT(*) FROM works WHERE rang = 2";
$sql3 = "SELECT COUNT(*) FROM works WHERE rang = 1";

$primer =  "SELECT id,name,foto FROM people WHERE id > 5 UNION ALL
 SELECT date,message FROM arhiv WHERE rang< 3";

$vajen = mysql_query($primer);