SQL LAST() 函数
LAST() 函数返回指定的列中最后一个记录的值。
1. SQL LAST() 语法
SELECT LAST(column_name) FROM table_name;
注释:只有 MS Access 支持 LAST() 函数。
1)SQL Server 语法
SELECT TOP 1 column_name
FROM table_name
ORDER BY column_name DESC;
ORDER BY column_name DESC;
2)MySQL 语法
SELECT column_name FROM table_name
ORDER BY column_name DESC
LIMIT 1;
ORDER BY column_name DESC
LIMIT 1;
3)Oracle 语法
SELECT column_name FROM table_name
ORDER BY column_name DESC
WHERE ROWNUM <=1;
ORDER BY column_name DESC
WHERE ROWNUM <=1;
样本数据库
在本教程中,我们将使用 Codebaoku 样本数据库。
下面是选自 "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 | 编程宝库 | http://www.codebaoku.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 | +----+---------------+---------------------------+-------+---------+
2. LAST() 范例
下面的 SQL 语句选取 "Websites" 表的 "name" 列中最后一个记录的值:
SELECT name FROM Websites ORDER BY id DESC LIMIT 1; 执行结果: +-------------------+ | name | +-------------------+ | stackoverflow | +-------------------+
MAX() 函数返回指定列的最大值。SQL MAX() 语法:SELECT MAX(column_name) FROM table_name; 在本教程中,我们将使用 CodeBaoku 样本数据库。