上篇博文介紹瞭如何安裝MySQL，本文會對如何操作MySQL數據庫進行介紹。首先登陸進入mysql>狀態。
1 在mysql>狀態下，輸入命令：
help 或 help contents
可以得到很多幫助信息：
Help
Note that all text commands must be firston line and end with ';'
? (\?) Synonym for `help'.
clear (\c) Clear the current input statement.
connect (\r) Reconnect to the server. Optional arguments are db and host.
Delimiter (\d) Set statement delimiter.
ego (\G) Send command to mysql server, display result vertically.
exit (\q) Exit mysql. Same as quit.
go (\g) Send command to mysql server.
help (\h) Display this help.
notee (\t) Don't write into outfile.
print (\p) Print current command.
prompt (\R) Change your mysql prompt.
quit (\q) Quit mysql.
rehash (\#) Rebuild completion hash.
source (\.) Execute an SQL script file. Takes a file name as an argument.
status (\s) Get status information from the server.
tee (\T) Set outfile [to_outfile]. Append everything into given outfile.
use (\u) Use another database. Takesdatabase name as argument.
charset (\C) Switch to another charset. Might be needed for processing binlogwith multi-byte charsets.
warnings (\W) Show warnings after every statement.
Nowarning (\w) Don't show warnings after every statement.
Resetconnection (\x) Clean session context.
【注意，每行命令必須以分號結束。】
Help contents
For more information, type 'help<item>', where <item> is one of the following
categories:
Account Management
Administration
Compound Statements
Data Definition
Data Manipulation
Data Types
Functions
Functions and Modifiers for Use with GROUP BY
Geographic Features
Help Metadata
Language Structure
Plugins
Procedures
Storage Engines
Table Maintenance
Transactions
User-Defined Functions
Utility
mysql> help Account Management
You asked for help about help category:"Account Management"
For more information, type 'help<item>', where <item> is one of the following
topics:
ALTER USER
CREATE USER
DROP USER
GRANT
RENAME USER
REVOKE
SET PASSWORD
2 建立mysql賬戶
Mysql 有一個默認數據庫：
輸入命令：
use mysql;
select * from user ;
可以看到裏面存儲的用戶信息，包括很多字段。
示例輸出：
命令：select host,user,select_priv,insert_priv from user ;
3 創建用戶：
mysql> insert into user(host,user,authentication_string,select_priv,insert_priv,update_priv,ssl_cipher,x509_issuer,x509_subject)values('localhost','luise2','luise222','y','y','y','y','y','y');
Query OK, 1 row affected (0.05 sec)
查詢如下：
使用PASSWORD()函數對密碼加密
insert into user(host,user,authentication_string,select_priv,insert_priv,update_priv,ssl_cipher,x509_issuer,x509_subject)values('localhost','luise3',PASSWORD('luise333'),'y','y','y','y','y','y');
【注意，我們使用FLUSH PRIVILEGES 語句，讓服務器重新加載授權表。就可以立馬使用新賬戶連接賬戶】
下面列出了一些重要且經常會用到的MySQL命令：
USE Databasename 用於在MySQL工作區內選擇具體某個數據庫。
SHOW DATABASES 列出 MySQL DBMS 所能訪問的數據庫。
SHOW TABLES 一旦數據庫被 use 命令選中，顯示數據庫中的表。
SHOW COLUMNS FROM tablename 顯示錶的屬性、屬性類型、鍵信息、是否允許 NULL 值，默認值，以及其他一些信息。
SHOW INDEX FROM tablename 顯示錶中所有索引的細節信息，包括PRIMARY KEY。
SHOW TABLE STATUS LIKE tablename\G 報告MySQL DBMS的性能及統計的細節信息。 【注意表名必須加單引號，不然會出錯】
