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>