MySQL数据库基础篇之入门基础命令小结

mysql> help create;
Many help items for your request exist.
To make a more specific request, please type 'help <item>',
where <item> is one of the following
topics:
 CREATE DATABASE #最简单的创建命令
 CREATE EVENT
 CREATE FUNCTION
 CREATE FUNCTION UDF
 CREATE INDEX
 CREATE LOGFILE GROUP
 CREATE PROCEDURE
 CREATE SERVER
 CREATE TABLE
 CREATE TABLESPACE
 CREATE TRIGGER
 CREATE USER
 CREATE VIEW
 SHOW
 SHOW CREATE DATABASE
 SHOW CREATE EVENT
 SHOW CREATE FUNCTION
 SHOW CREATE PROCEDURE
 SHOW CREATE TABLE
 SPATIAL

mysql> create database test_data;
#创建默认字符集的数据库（默认是拉丁字符集）
Query OK, 1 row affected (0.02 sec)
mysql> show databases like "test%";
+------------------+
| Database (test%) |
+------------------+
| test_data  |
+------------------+
1 rows in set (0.00 sec)

mysql> create database test_gbk DEFAULT CHARACTER SET gbk COLLATE gbk_chinese_ci;
Query OK, 1 row affected (0.04 sec)
mysql> show create database test_gbk; 
#查看创建数据库的语句
+----------+----------------------------------------------+
| Database | Create Database        |
+----------+------------------------------------------------------------------+
| test_gbk | CREATE DATABASE `test_gbk` /*!40100 DEFAULT CHARACTER SET gbk */ |
+----------+----------------------------------------------+
1 row in set (0.00 sec)

mysql> drop database test_data;
Query OK, 0 rows affected (0.07 sec)
mysql> show databases;
+----------------------------+
| Database     |
+----------------------------+
| information_schema |
| test_gbk     |
+----------------------------+

mysql> use test_gbk;
#相当于cd命令，切换到数据库进行操作
Database changed
mysql> select database();
#查看当前连接的数据库，相当于pwd
+------------+
| database() |
+------------+
| test_gbk |
+------------+
1 row in set (0.00 sec)
mysql> select user();

#查看当前连接数据库的用户,相当于whoami
+--------------------+
| user()    |
+-------------------+
| root@localhost |
+--------------------+
1 row in set (0.00 sec)

mysql> grant all on test_gbk.* to 'testuser'@'localhost' identified by '123456';
#创建用户并all权限给在test_gbk库所有表，密码‘123456'
Query OK, 0 rows affected (0.00 sec)
mysql> flush privileges;
#刷新权限，使权限生效
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for 'testuser'@'localhost';
#查看用户有哪些权限
+-----------------------------------------------------------------------------------------------------------------+
| Grants for testuser@localhost       |
+-----------------------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'testuser'@'localhost' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9' |
| GRANT ALL PRIVILEGES ON `test_gbk`.* TO 'testuser'@'localhost'         |
+-----------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

mysql> revoke insert,update,select,delete on test_gbk.* from 'testuser'@'localhost';
#将以上权限收回
Query OK, 0 rows affected (0.00 sec)
mysql> show grants for 'testuser'@'localhost';    
+----------------------------------------------------------------------------------------------------+
| Grants for testuser@localhost       |
+----------------------------------------------------------------------------------------------------+
| GRANT USAGE ON *.* TO 'testuser'@'localhost' IDENTIFIED BY PASSWORD '*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9'   |
| GRANT CREATE, DROP, REFERENCES, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, EVENT, TRIGGER ON `test_gbk`.* TO 'testuser'@'localhost' |
+------------------------------------------------------------------------------------------------------------------------------+
2 rows in set (0.00 sec)

mysql> create table test(id int(4)not null,name char(20)not null);
#建表，并且建立两个字段
Query OK, 0 rows affected (0.06 sec)
mysql> show tables;#查看表
+--------------------+
| Tables_in_test_gbk |
+--------------------+
| test      |
+--------------------+
1 row in set (0.00 sec)
mysql> desc test; #查看表结构
+-------+----------+------+-----+---------+-------+
| Field | Type  | Null | Key | Default | Extra |
+-------+----------+------+-----+---------+-------+
| id | int(4) | NO |  | NULL |  |
| name | char(20) | NO |  | NULL |  |
+-------+----------+------+-----+---------+-------+
2 rows in set (0.01 sec)

mysql> create table test1(id int(4)not null,name char(20)not null);
Query OK, 0 rows affected (0.01 sec)
mysql> show tables;
+------------------------+
| Tables_in_test_gbk |
+------------------------+
| test      |
| test1      |
+--------------------+
2 rows in set (0.00 sec)

mysql> drop tables test;
Query OK, 0 rows affected (0.00 sec)
mysql> show tables;
+--------------------+
| Tables_in_test_gbk |
+--------------------+
| test1     |
+--------------------+
1 row in set (0.00 sec)

mysql> show create table test1\G
*************************** 1. row ***************************
  Table: test1
Create Table: CREATE TABLE `test1` (
 `id` int(4) NOT NULL,
 `name` char(20) NOT NULL
) ENGINE=MyISAM DEFAULT CHARSET=gbk
1 row in set (0.00 sec)