MySQL account names consist of a user name and a host name, The name 'localhost' in host name indicates the local host also You can use the wildcard characters “%” and “_” in host name or IP address values. These have the same meaning as for pattern-matching operations performed with the LIKE operator. For example, a host value of '%' matches any host name, whereas a value of '%.mysql.com' matches any host in the mysql.com domain. '192.168.1.%' matches any host in the 192.168.1 class C network.

以上只是介绍:

实际上，用户“bill”@“localhost”和“bill”@“%”是不同的MySQL帐户，因此两者都应该使用自己的身份验证细节，如密码。

欲了解更多信息，请参阅http://dev.mysql.com/doc/refman//5.5/en/account-names.html

I discovered yet another case that appears on the surface to be an edge case; I can export to the file system, via SELECT INTO .. OUTFILE as root, but not as regular user. While this may be a matter of permissions, I've looked at that, and see nothing especially obvious. All I can say is that executing the query as a regular user who has all permissions on the data base in question returns the access denied error that led me to this topic. When I found the transcript of a successful use of SELECT INTO … OUTFILE in an old project, I noticed that I was logged in as root. Sure enough, when I logged in as root, the query ran as expected.

所以对我来说，这个问题与我映射的端口有关。

3306 => 3306不工作(因为我有一个本地mysql运行)

3307 => 3306工作!

这是在建立ssh隧道的上下文中:

ssh -N -L 3307:rdsDns:3306 ec2User@ec2Dns -i key.pem -v

3307为本端端口，3306为远端端口。

我也有同样的问题，但在我的情况下，解决方案是由eggyal的评论解决的。我也有一个匿名用户，但删除它并不能解决问题。'FLUSH PRIVILEGES'命令仍然有效。

让我感到惊讶的是，我用MySQL Workbench创建了这个用户，我本来希望它能执行完成任务所需的所有功能。

当你逃离

mysql -u bill -p

得到了这个错误

ERROR 1045 (28000): Access denied for user 'bill'@'localhost' (using password: YES)

Mysqld希望您以bill@localhost的身份连接

尝试创建bill@localhost

CREATE USER bill@localhost IDENTIFIED BY 'passpass';
grant all privileges on *.* to bill@localhost with grant option;

如果要远程连接，必须指定DNS名称、公共IP或127.0.0.1，使用TCP/IP:

mysql -u bill -p -hmydb@mydomain.com
mysql -u bill -p -h10.1.2.30
mysql -u bill -p -h127.0.0.1 --protocol=TCP

登录后，请运行这个

SELECT USER(),CURRENT_USER();

USER()报告您如何尝试在MySQL中进行身份验证

CURRENT_USER()报告你如何被允许从MySQL认证MySQL。用户表

这将使您更好地了解如何以及为什么允许您登录mysql。为什么知道这个观点很重要?它与用户身份验证排序协议有关。

下面是一个例子:我将在我的桌面MySQL上创建一个匿名用户

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
| lwdba   | %         |
| mywife  | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
7 rows in set (0.00 sec)

mysql> grant all on *.* to x@'%';
Query OK, 0 rows affected (0.02 sec)

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
| lwdba   | %         |
| mywife  | %         |
| x       | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
8 rows in set (0.00 sec)

mysql> update mysql.user set user='' where user='x';
Query OK, 1 row affected (0.00 sec)
Rows matched: 1  Changed: 1  Warnings: 0

mysql> flush privileges;
Query OK, 0 rows affected (0.01 sec)

mysql> select user,host from mysql.user;
+---------+-----------+
| user    | host      |
+---------+-----------+
|         | %         |
| lwdba   | %         |
| mywife  | %         |
| lwdba   | 127.0.0.1 |
| root    | 127.0.0.1 |
| lwdba   | localhost |
| root    | localhost |
| vanilla | localhost |
+---------+-----------+
8 rows in set (0.00 sec)

mysql>

好吧，看我以匿名用户登录:

C:\MySQL_5.5.12>mysql -urol -Dtest -h127.0.0.1 --protocol=TCP
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 12
Server version: 5.5.12-log MySQL Community Server (GPL)

Copyright (c) 2000, 2010, 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> select user(),current_user();
+---------------+----------------+
| user()        | current_user() |
+---------------+----------------+
| rol@localhost | @%             |
+---------------+----------------+
1 row in set (0.00 sec)

mysql>

认证顺序非常严格。它从最具体的到最不具体的。我在DBA StackExchange中写过这种身份验证样式。

不要忘记在必要时显式地调用TCP作为mysql客户端的协议。

对于Mac用户，如果他们仍然有问题(就像我的情况)，我发现这个解决方案为我工作:MySQL命令行'-bash命令未找到'

使用命令，即mysql在macbook终端上，你需要导出路径使用:

export PATH=$PATH:/usr/local/mysql/bin/

考虑默认安装，以root用户使用以下命令获取mysql提示符:

mysql -u root

否则您使用了错误的根密码。

参考:在OSX上设置MySQL root用户密码