MySQL学习足迹记录10--汇总数据--MAX(),MIN(),AVG(),SUM(),COUNT()(二)

  eg:
   mysql> SELECT COUNT(*) AS num_items,
            -> MIN(prod_price) AS price_min,
           -> MAX(prod_price) AS price_min,
           -> AVG(prod_price) AS price_avg
           -> FROM products;
+-----------+-----------+-----------+-----------+
| num_items | price_min | price_min | price_avg |
+-----------+-----------+-----------+-----------+
|        14 |      2.50 |     55.00 | 16.133571 |
+-----------+-----------+-----------+-----------+
1 row in set (0.00 sec)