MAX() 函数
MAX() 函数返回指定列的最大值。
SQL MAX() 语法
SELECT MAX(column_name) FROM table_name;
演示数据库
在猿变手册教程中,我们将使用 yuanbian 样本数据库。
下面是选自 "orders" 表的数据:
+----------+--------------+----------+--------------+----------------+---------------------+
| order_id | order_no | goods_id | order_amount | order_quantity | create_date |
+----------+--------------+----------+--------------+----------------+---------------------+
| 1 | 201503120001 | 10 | 1000 | 10 | 2015-03-12 09:00:04 |
| 2 | 201503120002 | 12 | 1300 | 12 | 2015-03-12 17:23:10 |
| 3 | 201503130001 | 11 | 2400 | 22 | 2015-03-13 10:30:12 |
| 4 | 201503130002 | 12 | 2500 | 15 | 2015-03-13 11:00:05 |
| 5 | 201503130003 | 10 | 1400 | 15 | 2015-03-13 14:54:00 |
| 6 | 201503140001 | 12 | 2100 | 12 | 2015-03-14 11:34:00 |
+----------+--------------+----------+--------------+----------------+---------------------+
SQL MAX() 示例
下面的 SQL 语句从 "orders" 表的 "order_amount" 列获取最大值, 即订单金额最高的订单记录:
SELECT order_id, MAX(order_amount) AS max_order
FROM orders;
执行以上 SQL 结果如下所示:
+----------+-----------+
| order_id | max_order |
+----------+-----------+
| 1 | 2500 |
+----------+-----------+
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