这里我怕大家理解不是很清楚，就特意来解释下吧，第一个是说我们可以导出一个数据库，也可以导出一个数据库下的表，第二个是说我们可以导出n多个数据库，但是需要加上--databases来说明，第三个则直接导出所有数据库。

既然有备份，就会有恢复，我们使用mysql命令即可，比如我创建一个an数据库，它使用咱们备份的文件中的数据，咱们看下面操作，我就不单个演示了，这里咱们的数据库an就拿到了我们的备份数据，顺便说一下，这个数据库an必须提前建好，它不具有自己创建新数据库的能力：

C:\Users\Administrator>mysql -u root -proot an < D:\my.sql
mysql: [Warning] Using a password on the command line interface can be insecure.

C:\Users\Administrator>mysql -u root -proot
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 124
Server version: 5.7.3-m13 MySQL Community Server (GPL)

Copyright (c) 2000, 2013, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> use an
Database changed
mysql> show tables;
+---------------------------+
| Tables_in_an              |
+---------------------------+
| columns_priv              |
| db                        |
| event                     |
| func                      |
| general_log               |
| help_category             |
| help_keyword              |
| help_relation             |
| help_topic                |
| innodb_index_stats        |
| innodb_table_stats        |
| ndb_binlog_index          |
| plugin                    |
| proc                      |
| procs_priv                |
| proxies_priv              |
| servers                   |
| slave_master_info         |
| slave_relay_log_info      |
| slave_worker_info         |
| slow_log                  |
| tables_priv               |
| time_zone                 |
| time_zone_leap_second     |
| time_zone_name            |
| time_zone_transition      |
| time_zone_transition_type |
| user                      |
+---------------------------+
28 rows in set (0.00 sec)

mysql>