mysql关键字不区分大小写

下列mysql查询是等价的：

mysql>
mysql>
mysql> SELECT VERSION();
+---------------------+
| VERSION()           |
+---------------------+
| 5.0.41-community-nt |
+---------------------+
1 row in set (0.00 sec)

mysql> select version();
+---------------------+
| version()           |
+---------------------+
| 5.0.41-community-nt |
+---------------------+
1 row in set (0.00 sec)

mysql> SeLeCt vErSiOn();
+---------------------+
| vErSiOn()           |
+---------------------+
| 5.0.41-community-nt |
+---------------------+
1 row in set (0.00 sec)

mysql>