如何获取mysql帮助信息

获取mysql有关的帮助信息，直接在mysql提示符下输入help即可获得有关在mysql客户端相关的帮助信息。

这个方式与Oracle SQL*plus下的help 是类似的。

mysql>help

For information about MySQL products and services, visit:

http://www.mysql.com/

For developer information, including the MySQL Reference Manual, visit:

http://dev.mysql.com/

To buy MySQL Enterprise support, training, or other products, visit:

https://shop.mysql.com/

List of all MySQL commands:

Note that all text commands must be first on line and end with ''

? (\?) Synonym for `help'.

clear (\c) Clear the current input statement. --清除当前输入的语句

connect (\r) Reconnect to the server. Optional arguments are db and host. --重新连接，通常用于被剔除或异常断开后重新连接，SQL*plus下也有这样一个connect命令

delimiter (\d) Set statement delimiter. --设置命令终止符，缺省为；，比如我们可以设定为/来表示语句结束

edit (\e) Edit command with $EDITOR. --编辑缓冲区的上一条SQL语句到文件，缺省调用vi，文件会放在/tmp路径下

ego (\G) Send command to mysql server, display result vertically. --控制结果显示为垂直显示

exit (\q) Exit mysql. Same as quit. --退出mysql

go(\g) Send command to mysql server. --发送命令到mysql服务

help (\h) Display this help.

nopager (\n) Disable pager, print to stdout.--关闭页设置，打印到标准输出

notee (\t) Don't write into outfile. --关闭输出到文件

pager (\P) Set PAGER [to_pager]. Print the query results via PAGER. --设置pager方式，可以设置为调用more,less等等，主要是用于分页显示

print (\p) Print current command.

prompt(\R) Change your mysql prompt. --改变mysql的提示符

quit (\q) Quit mysql.

rehash(\#) Rebuild completion hash. --自动补齐相关对象名字

source(\.) Execute an SQL script file. Takes a file name as an argument. --执行脚本文件

status(\s) Get status information from the server.--获得状态信息

system(\!) Execute a system shell command.--执行系统命令

tee (\T) Set outfile [to_outfile]. Append everything into given outfile.-- *** 作结果输出到文件

use (\u) Use another database. Takes database name as argument. --切换数据库

charset (\C) Switch to another charset. Might be needed for processing binlog with multi-byte charsets. --设置字符集

warnings (\W) Show warnings after every statement. --打印警告信息

nowarning (\w) Don't show warnings after every statement.

--上面的所有命令，扩号内的为快捷 *** 作，即只需要输入“\”+ 字母即可执行

For server side help, type 'help contents'--注意这里的描述help contents将获得服务器端的相关帮助信息

--演示部分，演示常用命令

--connect命令

mysql>connect chardb localhost

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Connection id:5

Current database: chardb

--设置分页，在多余一个页面显示时会不停的翻滚，用该命令可以设置分页，设置为调用系统命令

mysql>pager more --设置为more方式

PAGER set to 'more'

mysql>select table_name,table_type,engine from information_schema.tables --该查询会超出一屏显示后按空格键会自动翻滚到下一屏

mysql>pager tail -5 --设置输出尾部5行

PAGER set to 'tail -5'

mysql>select table_name,table_type,engine from information_schema.tables

| setup_timers | BASE TABLE | PERFORMANCE_SCHEMA |

| threads | BASE TABLE | PERFORMANCE_SCHEMA |

| animals | BASE TABLE | InnoDB |

| shop | BASE TABLE | InnoDB |

+----------------------------------------------+-------------+--------------------+

92 rows in set (0.02 sec)

mysql>pager --查看当前的pager设置

PAGER set to 'tail -5'

mysql>nopager --切换到标准(缺省)pager方式

PAGER set to stdout

--tee命令，输出日志文件

mysql>tee /tmp/query.log--开启输出到文件，相当与SQL*plus下的spool

Logging to file '/tmp/query.log'

mysql>select table_name,table_type,engine from information_schema.tables

+----------------------------------------------+-------------+--------------------+

| table_name | table_type | engine |

+----------------------------------------------+-------------+--------------------+

| CHARACTER_SETS | SYSTEM VIEW | MEMORY |

| COLLATIONS | SYSTEM VIEW | MEMORY |

.............

mysql>notee --关闭输出到文件，相当于SQL*Plus下的spool off

Outfile disabled.

mysql>system tail /tmp/query.log--查看输出的日志文件

| setup_consumers | BASE TABLE | PERFORMANCE_SCHEMA |

| setup_instruments| BASE TABLE | PERFORMANCE_SCHEMA |

| setup_timers | BASE TABLE | PERFORMANCE_SCHEMA |

| threads | BASE TABLE | PERFORMANCE_SCHEMA |

| animals | BASE TABLE | InnoDB |

| shop | BASE TABLE | InnoDB |

+----------------------------------------------+-------------+--------------------+

92 rows in set (0.02 sec)

--改变mysql提示符

mysql>prompt SessionA>

PROMPT set to 'SessionA>'

--恢复到缺省提示符

SessionA>prompt

Returning to default PROMPT of mysql>

--执行sql脚本文件

mysql>system more query.sql --注意，此时为当前目录

use chardb

select * from tb_isam

mysql>source query.sql

Reading table information for completion of table and column names

You can turn off this feature to get a quicker startup with -A

Database changed

+------+-------+

| id | value |

+------+-------+

|1 | a |

|2 | b |

|3 | c |

|4 | f |

+------+-------+

4 rows in set (0.00 sec)

--获取状态信息

mysql>status

--------------

mysql Ver 14.14 Distrib 5.5.37, for Linux (x86_64) using readline 5.1

Connection id: 6

Current database: chardb

Current user: root@localhost

SSL:Not in use

Current pager: less

Using outfile: ''

Using delimiter:

Server version: 5.5.37-log MySQL Community Server (GPL)

Protocol version: 10

Connection: Localhost via UNIX socket

Server characterset:latin1

Db characterset:utf8

Client characterset:latin1

Conn. characterset:latin1

UNIX socket:/var/lib/mysql/mysql.sock

Uptime: 3 hours 10 min 59 sec

Threads: 1 Questions: 97 Slow queries: 0 Opens: 313 Flush tables: 1 Open tables: 51 Queries per second avg: 0.008

--------------

--修改客户端字符集

想知道linux下怎么修改密码吗?下面由我为大家整理了linux mysql修改密码命令，希望大家喜欢!

　 　linux mysql修改密码命令

　 　1.修改root密码

linux mysql修改密码命令方法1：使用mysqladmin命令

--适用于记得root旧密码，修改root密码

语法：

mysqladmin -u用户名 -p旧密码 password 新密码

例如：

# mysqladmin -u root -proot password mysql

--注意：如当旧密码输入错误时会报如下错误

# mysqladmin -u root -proot1 password mysql

mysqladmin: connect to server at 'localhost' failed

error: 'Access denied for user 'root'@'localhost' (using password: YES)'

linux mysql修改密码命令方法2：直接更新user表password字段

--适用于忘记root密码，而对root密码进行重置

Step 1: 修改MySQL的登录设置

# vi /etc/my.cnf

--windows系统是my.ini文件

--在[mysqld]的段中加上一句：skip-grant-tables，如没有[mysqld]字段，可手动添加上

[mysqld]

datadir=/var/lib/mysql

socket=/var/lib/mysql/mysql.sock

skip-name-resolve

skip-grant-tables

Step 2: 重新启动mysql

[root@gc ~]# service mysql restart

Shutting down MySQL..[确定]

Starting MySQL...[确定]

Step 3: 登录并修改MySQL的root密码

--此时直接用mysql即可无需密码即可进入数据库了

[root@gc ~]# mysql

Welcome to the MySQL monitor. Commands end with or \g.

Your MySQL connection id is 2

Server version: 5.5.24 MySQL Community Server (GPL)

Copyright (c) 2000, 2011, 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 mysql

Database changed

mysql>update user set password=password('new_password') where user='root'

Query OK, 5 rows affected (0.00 sec)

Rows matched: 5 Changed: 5 Warnings: 0

mysql>flush privileges

Query OK, 0 rows affected (0.00 sec)

--注意：如果没做step1，直接用mysql登录时会报如下错误

[root@gc ~]# mysql

ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)

Step 4: 将MySQL的登录设置修改回来

再删除/etc/my.cnf文件中的skip-grant-tables

Step 5: 重新启动mysql

[root@gc ~]# service mysql restart

Shutting down MySQL..[确定]

Starting MySQL...[确定]

　 　2.修改mysql其它用户密码

同样，普通用户也可以用上面的方法

--使用mysqladmin命令

[root@njdyw ~]# mysqladmin -u user1 -ppass1 password pass2

--直接修改数据库表

[root@njdyw ~]# mysql -u user1 -ppass1 –Dmysql

mysql>update user set password=password('pass2') where user='user1'

mysql>flush privileges

---