FIRST() 函数

FIRST() 函数

返回指定的列中第一个记录的值。

SQL FIRST() 语法

SELECT FIRST(column_name) FROM table_name;

注释 ： 只有 MS Access 支持 FIRST() 函数。

SQL Server、MySQL 和 Oracle 中的 SQL FIRST() 工作区

SQL Server 语法

SELECT TOP 1 column_name FROM table_name
ORDER BY column_name ASC;

示例

SELECT TOP 1 name FROM Websites
ORDER BY id ASC;

MySQL 语法

SELECT column_name FROM table_name
ORDER BY column_name ASC
LIMIT 1;

示例

SELECT name FROM Websites
ORDER BY id ASC
LIMIT 1;

Oracle 语法

SELECT column_name FROM table_name
ORDER BY column_name ASC
WHERE ROWNUM <=1;

示例

SELECT name FROM Websites
ORDER BY id ASC
WHERE ROWNUM <=1;

示例

"Websites" 表的数据：

+----+--------------+---------------------------+-------+---------+
| id | name         | url                       | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1  | Google       | https://www.google.cm/    | 1     | USA     |
| 2  | 淘宝          | https://www.taobao.com/   | 13    | CN      |
| 3  | 菜鸟教程      | http://www.runoob.com/    | 4689  | CN      |
| 4  | 微博          | http://weibo.com/         | 20    | CN      |
| 5  | Facebook     | https://www.facebook.com/ | 3     | USA     |
|  6 | 百度         | https://www.baidu.com/    |     4 | CN      |
|  7 | stackoverflow | http://stackoverflow.com/ |     0 | IND     |
+----+---------------+---------------------------+-------+---------+

选取 "Websites" 表的 "name" 列中第一个记录的值：

SELECT name AS FirstSite FROM Websites LIMIT 1;

输出结果：

mysql> SELECT name AS FirstSite FROM Websites LIMIT 1;

+----+--------------+---------------------------+-------+---------+
| id | name         | url                       | alexa | country |
+----+--------------+---------------------------+-------+---------+
| 1  | Google       | https://www.google.cm/    | 1     | USA     |
+----+---------------+---------------------------+-------+---------+