mysql dumpfile 与 outfile 函数的区别

在windows下验一下这两个函数的区别

ubuntu下不成功，权限出错

mysql> select * from demo;
+-------------+--------------+
| first_field | second_field |
+-------------+--------------+
| ab          |            2 |
| abc         |            3 |
+-------------+--------------+
2 rows in set (0.00 sec)

mysql> select * from demo into outfile '/home/vigar/tst/aaa';
ERROR 1 (HY000): Can't create/write to file '/home/vigar/tst/aaa' (Errcode: 13)

mysql> create table a (cmd LONGBLOB);
Query OK, 0 rows affected (0.14 sec)

mysql> select * from a;
Empty set (0.00 sec)

mysql> insert into a (cmd) values (hex(load_file('/usr/bin/zip')));
Query OK, 1 row affected (0.00 sec)

mysql> select * from a;
+------+
| cmd  |
+------+
| NULL |
+------+
1 row in set (0.00 sec)

mysql> select unhex(cmd) from a into dumpfile './aaa';
Query OK, 1 row affected (0.00 sec)
但没有找到aaa的具体位置