[root@DBSVR01 e]# mysql -uroot -p
Enter password:
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: YES)
[root@DBSVR01 e]#
=======================
删除user.user中值为NULL的,或更新NULL为test 1)delete from user where user is NULL 2)update user set user=‘test‘ where user is NULL
=======================1
[root@DBSVR01 bin]# /etc/init.d/mysqld stop
Stopping mysqld: [ OK ]
[root@DBSVR01 bin]#
=======================2
别忘了最后的 &
[root@DBSVR01 ~]# mysqld_safe --user=mysql --skip-grant-tables --skip-networking &
[1] 4040
[root@DBSVR01 ~]# 130430 20:34:23 mysqld_safe Logging to '/var/log/mysqld.log'.
130430 20:34:23 mysqld_safe Starting mysqld daemon with databases from /var/lib/mysql
^C
[root@DBSVR01 ~]#
=======================3
[root@DBSVR01 ~]# mysql -u root mysql
Reading table information for completion of table and column names
You can turn off this feature to get a quicker startup with -A
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.1.69 Source distribution
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> update user set password=password('root') where user='root' and host='root' or host='localhost';
Query OK, 2 rows affected (0.01 sec)
Rows matched: 2 Changed: 2 Warnings: 0
mysql> flush privileges;
Query OK, 0 rows affected (0.00 sec)
mysql> quit
Bye
[root@DBSVR01 ~]# /etc/init.d/mysqld restart
130430 20:55:10 mysqld_safe mysqld from pid file /var/run/mysqld/mysqld.pid ended
Stopping mysqld: [ OK ]
Starting mysqld: [ OK ]
[1]+ Done mysqld_safe --user=mysql --skip-grant-tables --skip-networking
[root@DBSVR01 ~]# mysql -uroot -p
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.1.69 Source distribution
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> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| test |
+--------------------+
3 rows in set (0.00 sec)
mysql>quit
Bye
[root@DBSVR01 ~]# netstat -nat
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:53377 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp 0 196 168.168.80.8:22 168.168.80.1:17105 ESTABLISHED
tcp 0 0 :::111 :::* LISTEN
tcp 0 0 :::44691 :::* LISTEN
tcp 0 0 :::22 :::* LISTEN
tcp 0 0 ::1:631 :::* LISTEN
[root@DBSVR01 ~]#
在linux下可以用mysql命令登陆连接到mysql服务器，如果这时需要执行shell命令，例如查看某个目录下的文件列表，其实不需要退出mysql客户端，只需要在mysql提示符下输入system或\! 再加上系统命令即可
mysql> status
--------------
mysql Ver 14.14 Distrib 5.1.69, for redhat-linux-gnu (i386) using readline 5.1
Connection id: 3
Current database:
Current user: root@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ''
Using delimiter: ;
Server version: 5.1.69 Source distribution
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: latin1
Db characterset: latin1
Client characterset: latin1
Conn. characterset: latin1
UNIX socket: /var/lib/mysql/mysql.sock
Uptime: 8 min 53 sec
Threads: 1 Questions: 41 Slow queries: 0 Opens: 30 Flush tables: 1 Open tables: 23 Queries per second avg: 0.76
--------------
mysql>
mysql> system netstat -nat
Active Internet connections (servers and established)
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 0.0.0.0:53377 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:111 0.0.0.0:* LISTEN
tcp 0 0 0.0.0.0:22 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:631 0.0.0.0:* LISTEN
tcp 0 0 127.0.0.1:25 0.0.0.0:* LISTEN
tcp 0 52 168.168.80.8:22 168.168.80.1:17105 ESTABLISHED
tcp 0 0 :::111 :::* LISTEN
tcp 0 0 :::44691 :::* LISTEN
tcp 0 0 :::22 :::* LISTEN
tcp 0 0 ::1:631 :::* LISTEN
mysql>
我想应该是root在本地连接的原因，所以前面的地址是0.0.0.0，如果在另外的电脑上，通过TCP连过来，就应该有IP地址了。
mysql> \! ps -ef | grep mysql
root
4241 1 0 20:55 pts/1 00:00:00 /bin/sh /usr/bin/mysqld_safe
--datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock
--pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr -
mysql
4343 4241 0 20:55 pts/1 00:00:00 /usr/libexec/mysqld --basedir=/usr
--datadir=/var/lib/mysql --user=mysql --log-error=/var/log/mysqld.log
--pid-file=/var/run/mysqld/mysqld.pid
root 4391 4014 0 21:03 pts/1 00:00:00 mysql -uroot -p
root 4436 4391 0 21:22 pts/1 00:00:00 sh -c ps -ef | grep mysql
root 4438 4436 0 21:22 pts/1 00:00:00 grep mysql
mysql> \! ps -ef | grep mysql | grep -v grep
root
4241 1 0 20:55 pts/1 00:00:00 /bin/sh /usr/bin/mysqld_safe
--datadir=/var/lib/mysql --socket=/var/lib/mysql/mysql.sock
--pid-file=/var/run/mysqld/mysqld.pid --basedir=/usr -
mysql
4343 4241 0 20:55 pts/1 00:00:00 /usr/libexec/mysqld --basedir=/usr
--datadir=/var/lib/mysql --user=mysql --log-error=/var/log/mysqld.log
--pid-file=/var/run/mysqld/mysqld.pid
root 4391 4014 0 21:03 pts/1 00:00:00 mysql -uroot -p
mysql>