MySQL建表操作
[email protected] 08:05:22> create table stu( -> id int(4) not null, -> name char(20) not null, -> age tinyint(2) not null default ‘0‘, -> dept varchar(16) default null -> ); Query OK, 0 rows affected (0.01 sec) [email protected] 08:07:20> [email protected] 08:07:21> show tables; +----------------+ | Tables_in_test | +----------------+ | stu | +----------------+ 1 row in set (0.00 sec) [email protected] 08:07:25> desc stu; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | id | int(4) | NO | | NULL | | | name | char(20) | NO | | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 4 rows in set (0.00 sec) [email protected] 08:07:28> [email protected] 08:07:28> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(4) NOT NULL, `name` char(20) NOT NULL, `age` tinyint(2) NOT NULL DEFAULT ‘0‘, `dept` varchar(16) DEFAULT NULL ) ENGINE=MyISAM DEFAULT CHARSET=latin1 1 row in set (0.00 sec) [email protected] 08:08:47>
mysql5.1及以前的默认引擎是MyISAM,MySQL5.5及以后的默认引擎的InnoDB
int 整数类型
char 定长字符串类型,存储时总是用空格填满右边到指定的长度
varchar 变长字符串类型
其他详细信息可以参考 MySQL手册
为表的字段添加索引
索引类似于书的目录,如果在字段上建立索引,那么以索引列为查询条件就可以加快查询数据的速度
[email protected] 08:38:25> create table student( -> id int(4) not null AUTO_INCREMENT, -> name char(20) not null, -> age tinyint(2) NOT NULL default ‘0‘, -> dept varchar(16) default NULL, -> primary key(id), -> KEY index_name (name) -> ); Query OK, 0 rows affected (0.00 sec) [email protected] 08:38:31> [email protected] 08:40:02> desc student; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(4) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 08:40:16> show create table student\G *************************** 1. row *************************** Table: student Create Table: CREATE TABLE `student` ( `id` int(4) NOT NULL AUTO_INCREMENT, `name` char(20) NOT NULL, `age` tinyint(2) NOT NULL DEFAULT ‘0‘, `dept` varchar(16) DEFAULT NULL, PRIMARY KEY (`id`), KEY `index_name` (`name`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 1 row in set (0.00 sec) [email protected] 08:40:18>
alter table 修改表结构
1.alter 增加主键索引
[email protected] 08:50:04> create table stu( -> id int(4) not null, -> name char(20) not null, -> age tinyint(2) NOT NULL default ‘0‘, -> dept varchar(16) default NULL, -> KEY index_name (name) -> ); Query OK, 0 rows affected (0.01 sec) [email protected] 08:50:05> show tables; +----------------+ | Tables_in_test | +----------------+ | stu | | student | +----------------+ 2 rows in set (0.00 sec) [email protected] 08:50:12> desc stu; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | id | int(4) | NO | | NULL | | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 4 rows in set (0.00 sec) [email protected] 08:50:15> alter table stu change id id int primary key auto_increment; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 08:51:16> desc stu; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 08:51:19>
2.alter删除主键索引(然后再添加主键索引)
[email protected] 08:53:30> create table stu1( -> id int(4) not null, -> name char(20) not null, -> age tinyint(2) NOT NULL default ‘0‘, -> dept varchar(16) default NULL, -> primary key(id), -> KEY index_name (name) -> ); Query OK, 0 rows affected (0.01 sec) [email protected] 08:53:54> desc stu1; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | id | int(4) | NO | PRI | NULL | | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 4 rows in set (0.00 sec) [email protected] 08:54:20> alter table stu1 drop primary key; Query OK, 0 rows affected (0.00 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 08:54:27> desc stu1; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | id | int(4) | NO | | NULL | | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 4 rows in set (0.01 sec) [email protected] 08:54:30> [email protected] 08:57:08> desc stu1; +-------+-------------+------+-----+---------+-------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+-------+ | id | int(4) | NO | | NULL | | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+-------+ 4 rows in set (0.00 sec) [email protected] 08:57:10> alter table stu1 change id id int primary key auto_increment; Query OK, 0 rows affected (0.02 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 08:57:32> desc stu1; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 08:57:34>
3.alter删除普通索引以及添加普通索引
[email protected] 09:06:31> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(20) NOT NULL, `age` tinyint(2) NOT NULL DEFAULT ‘0‘, `dept` varchar(16) DEFAULT NULL, PRIMARY KEY (`id`), KEY `index_name` (`name`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 1 row in set (0.00 sec) [email protected] 09:07:07> desc stu; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:07:15> alter table stu drop index index_name; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:07:29> desc stu; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:07:31> [email protected] 09:07:59> alter table stu add index index_dept(dept); Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:08:21> desc stu; +-------+-------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+-------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(16) | YES | MUL | NULL | | +-------+-------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:08:23>
4.alter 修改字段
[email protected] 09:08:23> alter table stu change dept dept varchar(200) not null default "TP"; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:10:25> desc stu; +-------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | +-------+--------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:10:28> [email protected] 09:10:28> alter table stu add index index_name(name); Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:11:38> desc stu; +-------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(20) | NO | MUL | NULL | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | +-------+--------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:11:39> alter table stu change name name char(50) not null default "Simon"; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:12:23> desc stu; +-------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | MUL | Simon | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | +-------+--------------+------+-----+---------+----------------+ 4 rows in set (0.00 sec) [email protected] 09:12:24> [email protected] 10:13:26> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | dept | varchar(200) | NO | MUL | TP | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 10:13:30> [email protected] 10:20:21> alter table stu change dept department varchar(200) NOT NULL DEFAULT ‘TP_cloud‘ COMMENT ‘谷歌部门信息‘; Query OK, 0 rows affected (0.02 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 10:20:24> [email protected] 10:20:33> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 10:20:42>
5.alter 添加列
[email protected] 09:19:41> alter table stu add column description longtext; Query OK, 0 rows affected (0.00 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:21:58> desc stu; +-------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | MUL | Simon | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | | description | longtext | YES | | NULL | | +-------------+--------------+------+-----+---------+----------------+ 5 rows in set (0.00 sec) [email protected] 09:22:00> alter table stu add column date datetime; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:22:54> desc stu; +-------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | MUL | Simon | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | | description | longtext | YES | | NULL | | | date | datetime | YES | | NULL | | +-------------+--------------+------+-----+---------+----------------+ 6 rows in set (0.01 sec) [email protected] 09:24:54> alter table stu change date date datetime not null comment ‘插入时间‘; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:24:58> [email protected] 09:24:58> desc stu; +-------------+--------------+------+-----+---------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+---------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | MUL | Simon | | | age | tinyint(2) | NO | | 0 | | | dept | varchar(200) | NO | MUL | TP | | | description | longtext | YES | | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+---------+----------------+ 6 rows in set (0.00 sec) [email protected] 09:27:22>
6.查看表字段的注释
[email protected] 09:35:21> select column_name,column_comment from information_schema.columns where table_name=‘stu‘ and table_schema=‘test‘; +-------------+----------------+ | column_name | column_comment | +-------------+----------------+ | id | | | name | | | age | | | dept | | | description | | | date | 插入时间 | +-------------+----------------+ 6 rows in set (0.00 sec) [email protected] 09:35:26> show full columns from stu\G 也可以
7.添加注释
- 给表添加注释
ALTER TABLE table_name COMMENT=‘这是表的注释‘;
- 给字段添加注释
alter table stu change column name name char(50) not null default ‘Simon Paul‘ comment ‘学生姓名字段注释‘;
8.对字段前n个字符创建索引
[email protected] 09:50:53> create index index_desc on stu(description(66)); Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:52:17> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | MUL | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | dept | varchar(200) | NO | MUL | TP | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 09:52:24> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(50) NOT NULL DEFAULT ‘Simon Paul‘ COMMENT ‘学生姓名字段注释‘, `age` tinyint(2) NOT NULL DEFAULT ‘23‘ COMMENT ‘年龄‘, `dept` varchar(200) NOT NULL DEFAULT ‘TP‘ COMMENT ‘单位信息‘, `description` longtext NOT NULL COMMENT ‘这个是学生描述信息字段的注释‘, `date` datetime NOT NULL COMMENT ‘插入时间‘, PRIMARY KEY (`id`), KEY `index_dept` (`dept`), KEY `index_name` (`name`), KEY `index_desc` (`description`(66)) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COMMENT=‘这是stu表的注释‘ 1 row in set (0.00 sec) [email protected] 09:52:28>
9.更该索引
MySQL并没有提供修改索引的直接指令,一般情况下,我们需要先删除掉原索引,再根据需要创建一个同名的索引,从而变相地实现修改索引操作
show index from stu\G
[email protected] 09:52:24> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(50) NOT NULL DEFAULT ‘Simon Paul‘ COMMENT ‘学生姓名字段注释‘, `age` tinyint(2) NOT NULL DEFAULT ‘23‘ COMMENT ‘年龄‘, `dept` varchar(200) NOT NULL DEFAULT ‘TP‘ COMMENT ‘单位信息‘, `description` longtext NOT NULL COMMENT ‘这个是学生描述信息字段的注释‘, `date` datetime NOT NULL COMMENT ‘插入时间‘, PRIMARY KEY (`id`), KEY `index_dept` (`dept`), KEY `index_name` (`name`), KEY `index_desc` (`description`(66)) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COMMENT=‘这是stu表的注释‘ 1 row in set (0.00 sec) [email protected] 09:52:28> alter table stu drop index index_name; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:56:30> create index index_name on stu(name(12)); Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 09:56:56> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(50) NOT NULL DEFAULT ‘Simon Paul‘ COMMENT ‘学生姓名字段注释‘, `age` tinyint(2) NOT NULL DEFAULT ‘23‘ COMMENT ‘年龄‘, `dept` varchar(200) NOT NULL DEFAULT ‘TP‘ COMMENT ‘单位信息‘, `description` longtext NOT NULL COMMENT ‘这个是学生描述信息字段的注释‘, `date` datetime NOT NULL COMMENT ‘插入时间‘, PRIMARY KEY (`id`), KEY `index_dept` (`dept`), KEY `index_desc` (`description`(66)), KEY `index_name` (`name`(12)) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COMMENT=‘这是stu表的注释‘ 1 row in set (0.00 sec) [email protected] 09:57:04>
10.为表的多个字段创建联合索引
create index index_name_dept on stu(name(8),dept);
11.删除索引
drop index index_name on stu;
12.创唯一索引(非主键)
create unique index uniq_index_name on stu(name);
Finnaly
[email protected] 10:25:54> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 10:25:58> show create table stu\G *************************** 1. row *************************** Table: stu Create Table: CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(50) NOT NULL DEFAULT ‘Simon Paul‘ COMMENT ‘学生姓名字段注释‘, `age` tinyint(2) NOT NULL DEFAULT ‘23‘ COMMENT ‘年龄‘, `department` varchar(200) NOT NULL DEFAULT ‘TP_cloud‘ COMMENT ‘谷歌部门信息‘, `description` longtext NOT NULL COMMENT ‘这个是学生描述信息字段的注释‘, `date` datetime NOT NULL COMMENT ‘插入时间‘, PRIMARY KEY (`id`), UNIQUE KEY `uniq_index_name` (`name`), KEY `index_dept` (`department`), KEY `index_desc` (`description`(66)), KEY `index_name_dept` (`name`(8),`department`) ) ENGINE=MyISAM DEFAULT CHARSET=latin1 COMMENT=‘这是stu表的注释‘ 1 row in set (0.00 sec) [email protected] 10:26:09>
alter添加字段到指定的位置
[email protected] 10:28:00> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 10:28:08> alter table stu add column sex tinyint(1) not null after description; Query OK, 0 rows affected (0.02 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 10:29:19> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | sex | tinyint(1) | NO | | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 7 rows in set (0.00 sec) [email protected] 10:29:21> [email protected] 10:29:57> alter table stu change column sex sex tinyint(1) not null default 1 after description; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 10:30:47> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | sex | tinyint(1) | NO | | 1 | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 7 rows in set (0.00 sec) ro[email protected] 10:30:53> [email protected] 10:30:53> alter table stu drop column sex; Query OK, 0 rows affected (0.01 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 10:33:39> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 6 rows in set (0.00 sec) [email protected] 10:33:45> [email protected] 10:33:45> alter table stu add column sex tinyint(1) not null default 1 before date; ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ‘before date‘ at line 1 [email protected] 10:34:24> alter table stu add column sex tinyint(1) not null default 1 first; Query OK, 0 rows affected (0.02 sec) Records: 0 Duplicates: 0 Warnings: 0 [email protected] 10:36:49> desc stu; +-------------+--------------+------+-----+------------+----------------+ | Field | Type | Null | Key | Default | Extra | +-------------+--------------+------+-----+------------+----------------+ | sex | tinyint(1) | NO | | 1 | | | id | int(11) | NO | PRI | NULL | auto_increment | | name | char(50) | NO | UNI | Simon Paul | | | age | tinyint(2) | NO | | 23 | | | department | varchar(200) | NO | MUL | TP_cloud | | | description | longtext | NO | MUL | NULL | | | date | datetime | NO | | NULL | | +-------------+--------------+------+-----+------------+----------------+ 7 rows in set (0.00 sec) [email protected] 10:36:51>
# 多查看帮助文档 help alter table
INSERT 和 UPDATE
[email protected] 10:44:46> insert into stu(name,age,department,description,date) values(‘Tim‘,39,‘Tencent‘,‘Connecting people for a greater future.‘,now()); Query OK, 1 row affected (0.00 sec) [email protected] 10:46:37> [email protected] 10:46:40> update stu set description=‘Just stick to what you love and belive in.‘ where name=‘Mark‘; Query OK, 1 row affected (0.00 sec) Rows matched: 1 Changed: 1 Warnings: 0 [email protected] 11:02:41> select * from stu; +----+------------------+-----+-------------+--------------------------------------------------+---------------------+ | id | name | age | department | description | date | +----+------------------+-----+-------------+--------------------------------------------------+---------------------+ | 1 | standby | 23 | live_cloud | Use ATS to archive the multiple level‘s cache. | 0000-00-00 00:00:00 | | 2 | Jefrriy | 25 | live_cloud | Use Squid to archive the multiple level‘s cache. | 0000-00-00 00:00:00 | | 3 | Mark | 47 | Mindjet | Just stick to what you love and belive in. | 2017-03-12 10:43:56 | | 4 | Frankyang | 35 | Google | DNS administrator | 2017-03-12 10:44:46 | | 5 | Tim | 39 | Tencent | Connecting people for a greater future. | 2017-03-12 10:46:37 | | 6 | Michael Widenius | 43 | MariaDB inc | The Fastest Growing Open Source Database. | 2017-03-12 10:56:31 | +----+------------------+-----+-------------+--------------------------------------------------+---------------------+ 6 rows in set (0.00 sec) [email protected] 11:02:47>
MYSQLDUMP
[[email protected] ~]# mysqldump -uroot -p123456 -B test >/tmp/test_bak_20170312.sql [[email protected] ~]# ll /tmp/ total 8 -rw-r--r-- 1 root root 3236 Mar 12 11:01 test_bak_20170312.sql drwx------ 2 root root 4096 Sep 17 22:51 tmux-0 [[email protected] ~]# [[email protected] ~]# cat /tmp/test_bak_20170312.sql -- MySQL dump 10.13 Distrib 5.1.72, for unknown-linux-gnu (x86_64) -- -- Host: localhost Database: test -- ------------------------------------------------------ -- Server version 5.1.72 /*!40101 SET @[email protected]@CHARACTER_SET_CLIENT */; /*!40101 SET @[email protected]@CHARACTER_SET_RESULTS */; /*!40101 SET @[email protected]@COLLATION_CONNECTION */; /*!40101 SET NAMES utf8 */; /*!40103 SET @[email protected]@TIME_ZONE */; /*!40103 SET TIME_ZONE=‘+00:00‘ */; /*!40014 SET @[email protected]@UNIQUE_CHECKS, UNIQUE_CHECKS=0 */; /*!40014 SET @[email protected]@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */; /*!40101 SET @[email protected]@SQL_MODE, SQL_MODE=‘NO_AUTO_VALUE_ON_ZERO‘ */; /*!40111 SET @[email protected]@SQL_NOTES, SQL_NOTES=0 */; -- -- Current Database: `test` -- CREATE DATABASE /*!32312 IF NOT EXISTS*/ `test` /*!40100 DEFAULT CHARACTER SET latin1 */; USE `test`; -- -- Table structure for table `stu` -- DROP TABLE IF EXISTS `stu`; /*!40101 SET @saved_cs_client = @@character_set_client */; /*!40101 SET character_set_client = utf8 */; CREATE TABLE `stu` ( `id` int(11) NOT NULL AUTO_INCREMENT, `name` char(50) NOT NULL DEFAULT ‘Simon Paul‘ COMMENT ‘å¦ç”Ÿå§“åå—段注释‘, `age` tinyint(2) NOT NULL DEFAULT ‘23‘ COMMENT ‘年龄‘, `department` varchar(200) NOT NULL DEFAULT ‘TP_cloud‘ COMMENT ‘爱奇艺部门信毑, `description` longtext NOT NULL COMMENT ‘这个是å¦ç”Ÿæè¿°ä¿¡æ¯å—段的注释‘, `date` datetime NOT NULL COMMENT ‘æ’入时间‘, PRIMARY KEY (`id`), UNIQUE KEY `uniq_index_name` (`name`), KEY `index_dept` (`department`), KEY `index_desc` (`description`(66)), KEY `index_name_dept` (`name`(8),`department`) ) ENGINE=MyISAM AUTO_INCREMENT=7 DEFAULT CHARSET=latin1 COMMENT=‘这是stu表的注释‘; /*!40101 SET character_set_client = @saved_cs_client */; -- -- Dumping data for table `stu` -- LOCK TABLES `stu` WRITE; /*!40000 ALTER TABLE `stu` DISABLE KEYS */; INSERT INTO `stu` VALUES (1,‘standby‘,23,‘live_cloud‘,‘Use ATS to archive the multiple level\‘s cache.‘,‘0000-00-00 00:00:00‘),(2,‘Jefrriy‘,25,‘live_cloud‘,‘Use Squid to archive the multiple level\‘s cache.‘,‘0000-00-00 00:00:00‘),(3,‘Mark‘,47,‘Mindjet‘,‘Just stick to what you love and belive in.‘,‘2017-03-12 10:43:56‘),(4,‘Frankyang‘,35,‘Google‘,‘DNS administrator‘,‘2017-03-12 10:44:46‘),(5,‘Tim‘,39,‘Tencent‘,‘Connecting people for a greater future.‘,‘2017-03-12 10:46:37‘),(6,‘Michael Widenius‘,43,‘MariaDB inc‘,‘The Fastest Growing Open Source Database.‘,‘2017-03-12 10:56:31‘); /*!40000 ALTER TABLE `stu` ENABLE KEYS */; UNLOCK TABLES; /*!40103 SET [email protected]_TIME_ZONE */; /*!40101 SET [email protected]_SQL_MODE */; /*!40014 SET [email protected]_FOREIGN_KEY_CHECKS */; /*!40014 SET [email protected]_UNIQUE_CHECKS */; /*!40101 SET [email protected]_CHARACTER_SET_CLIENT */; /*!40101 SET [email protected]_CHARACTER_SET_RESULTS */; /*!40101 SET [email protected]_COLLATION_CONNECTION */; /*!40111 SET [email protected]_SQL_NOTES */; -- Dump completed on 2017-03-12 11:01:59 [[email protected] ~]#
降序/升序/limit
mysql> select user,host,password from mysql.user; +------+-----------+-------------------------------------------+ | user | host | password | +------+-----------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | +------+-----------+-------------------------------------------+ 2 rows in set (0.00 sec) mysql> select user,host,password from mysql.user order by user asc; +------+-----------+-------------------------------------------+ | user | host | password | +------+-----------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | +------+-----------+-------------------------------------------+ 2 rows in set (0.00 sec) mysql> select user,host,password from mysql.user order by user desc; +------+-----------+-------------------------------------------+ | user | host | password | +------+-----------+-------------------------------------------+ | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | +------+-----------+-------------------------------------------+ 2 rows in set (0.00 sec) mysql> select user,host,password from mysql.user order by user desc limit 1; +------+-----------+-------------------------------------------+ | user | host | password | +------+-----------+-------------------------------------------+ | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | +------+-----------+-------------------------------------------+ 1 row in set (0.00 sec) mysql>
like 模糊匹配
[email protected] 10:30:14> show databases; +--------------------+ | Database | +--------------------+ | information_schema | | No_wiki | | iQiYi | | mysql | | wiki | | wiki001 | | wiki002 | | wiki003 | +--------------------+ 8 rows in set (0.00 sec) [email protected] 10:30:20> show databases like ‘wiki%‘; +------------------+ | Database (wiki%) | +------------------+ | wiki | | wiki001 | | wiki002 | | wiki003 | +------------------+ 4 rows in set (0.00 sec) [email protected] 10:30:25>
常用函数
[email protected] 10:34:46> select database(); +------------+ | database() | +------------+ | wiki | +------------+ 1 row in set (0.00 sec) [email protected] 10:34:52> select user(); +----------------+ | user() | +----------------+ | [email protected] | +----------------+ 1 row in set (0.00 sec) [email protected] 10:34:56> select now(); +---------------------+ | now() | +---------------------+ | 2017-03-11 22:35:00 | +---------------------+ 1 row in set (0.01 sec) [email protected] 10:35:00> select version(); +-----------+ | version() | +-----------+ | 5.1.72 | +-----------+ 1 row in set (0.00 sec) [email protected] 10:35:05>
创建新用户并授权
只使用 grant
创建用户并授权
[email protected] 10:43:48> grant all privileges on iQiYi.* to ‘standby‘@‘localhost‘ identified by ‘liulixin‘; Query OK, 0 rows affected (0.01 sec) [email protected] 10:44:26> select user,host,password from user; +---------+-----------+-------------------------------------------+ | user | host | password | +---------+-----------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | | standby | localhost | *68400CF212112D85B99EB397ADCB27748218BFAE | +---------+-----------+-------------------------------------------+ 3 rows in set (0.00 sec) [email protected] 10:44:31> [email protected] 10:44:58> select user,host,password from user where user like ‘%and%‘; +---------+-----------+-------------------------------------------+ | user | host | password | +---------+-----------+-------------------------------------------+ | standby | localhost | *68400CF212112D85B99EB397ADCB27748218BFAE | +---------+-----------+-------------------------------------------+ 1 row in set (0.00 sec) [email protected] 10:45:12> grant all privileges on iQiYi.* to ‘standby‘@‘localhost‘ identified by ‘liulixin‘;
使用 create
和 grant
创建用户并授权
[email protected] 10:56:11> CREATE USER ‘standby001‘@‘localhost‘ IDENTIFIED BY ‘123456‘; Query OK, 0 rows affected (0.00 sec) [email protected] 10:56:38> GRANT ALL ON No_wiki.* TO ‘standby001‘@‘localhost‘; Query OK, 0 rows affected (0.00 sec) [email protected] 10:57:22> [email protected] 10:57:26> select user,host,password from mysql.user; +------------+-----------+-------------------------------------------+ | user | host | password | +------------+-----------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | | standby | localhost | *68400CF212112D85B99EB397ADCB27748218BFAE | | standby001 | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | +------------+-----------+-------------------------------------------+ 4 rows in set (0.00 sec) [email protected] 10:57:41> show grants for ‘standby001‘@‘localhost‘; +-------------------------------------------------------------------------------------------------------------------+ | Grants for [email protected] | +-------------------------------------------------------------------------------------------------------------------+ | GRANT USAGE ON *.* TO ‘standby001‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9‘ | | GRANT ALL PRIVILEGES ON `No_wiki`.* TO ‘standby001‘@‘localhost‘ | +-------------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) [email protected] 10:58:03> show grants for ‘standby001‘@‘localhost‘\G *************************** 1. row *************************** Grants for [email protected]: GRANT USAGE ON *.* TO ‘standby001‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9‘ *************************** 2. row *************************** Grants for [email protected]: GRANT ALL PRIVILEGES ON `No_wiki`.* TO ‘standby001‘@‘localhost‘ 2 rows in set (0.00 sec) [email protected] 10:58:06>
查看某个用户的授权情况
[email protected] 10:48:54> show grants for ‘standby‘@‘localhost‘; +----------------------------------------------------------------------------------------------------------------+ | Grants for [email protected] | +----------------------------------------------------------------------------------------------------------------+ | GRANT USAGE ON *.* TO ‘standby‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*68400CF212112D85B99EB397ADCB27748218BFAE‘ | | GRANT ALL PRIVILEGES ON `iQiYi`.* TO ‘standby‘@‘localhost‘ | +----------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) [email protected] 10:49:10> show grants for ‘standby‘@‘localhost‘\G *************************** 1. row *************************** Grants for [email protected]: GRANT USAGE ON *.* TO ‘standby‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*68400CF212112D85B99EB397ADCB27748218BFAE‘ *************************** 2. row *************************** Grants for [email protected]: GRANT ALL PRIVILEGES ON `iQiYi`.* TO ‘standby‘@‘localhost‘ 2 rows in set (0.00 sec) [email protected] 10:49:14>
授权局域网内主机远程连接数据库
[email protected] 11:07:07> grant all privileges on wiki.* to ‘remote_test‘@‘10.0.0.%‘ identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) [email protected] 11:08:40> flush privileges; Query OK, 0 rows affected (0.00 sec) [email protected] 11:08:46> select user,host,password from mysql.user; +-------------+-----------+-------------------------------------------+ | user | host | password | +-------------+-----------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | | standby | localhost | *68400CF212112D85B99EB397ADCB27748218BFAE | | standby001 | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | remote_test | 10.0.0.% | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | +-------------+-----------+-------------------------------------------+ 5 rows in set (0.00 sec) [email protected] 11:08:48> [email protected] 11:08:48> grant all privileges on wiki.* to ‘remote_test001‘@‘10.0.0.0/24‘ identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) [email protected] 11:10:39> grant all privileges on wiki.* to ‘remote_test002‘@‘10.0.0.0/255.255.255.0‘ identified by ‘123456‘; Query OK, 0 rows affected (0.00 sec) [email protected] 11:11:19> flush privileges; Query OK, 0 rows affected (0.01 sec) [email protected] 11:11:20> select user,host,password from mysql.user; +----------------+------------------------+-------------------------------------------+ | user | host | password | +----------------+------------------------+-------------------------------------------+ | root | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | wiki | localhost | *A5DB2D927D6DF94DA5E1CE4B293AEAAB4D8304EA | | standby | localhost | *68400CF212112D85B99EB397ADCB27748218BFAE | | standby001 | localhost | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | remote_test | 10.0.0.% | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | remote_test001 | 10.0.0.0/24 | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | | remote_test002 | 10.0.0.0/255.255.255.0 | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9 | +----------------+------------------------+-------------------------------------------+ 7 rows in set (0.00 sec) [email protected] 11:11:49>
grant all privileges on wiki.* to ‘remote_test‘@‘10.0.0.%‘ identified by ‘123456‘;
可用grant all privileges on wiki.* to ‘remote_test002‘@‘10.0.0.0/255.255.255.0‘ identified by ‘123456‘;
可用grant all privileges on wiki.* to ‘remote_test001‘@‘10.0.0.0/24‘ identified by ‘123456‘;
不可用
远端连接的命令:
mysql -u remote_test -h 10.0.0.9 -p123456
-P 指定端口
INVOKE收回某个授权/反向查看ALL PRIVILEGES都有哪些具体权限
[email protected] 11:24:12> show grants for ‘standby‘@‘localhost‘; +----------------------------------------------------------------------------------------------------------------+ | Grants for [email protected] | +----------------------------------------------------------------------------------------------------------------+ | GRANT USAGE ON *.* TO ‘standby‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*68400CF212112D85B99EB397ADCB27748218BFAE‘ | | GRANT ALL PRIVILEGES ON `iQiYi`.* TO ‘standby‘@‘localhost‘ | +----------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) [email protected] 11:24:16> REVOKE INSERT ON `iQiYi`.* FROM ‘standby‘@‘localhost‘; Query OK, 0 rows affected (0.00 sec) [email protected] 11:28:27> show grants for ‘standby‘@‘localhost‘; +----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | Grants for [email protected] | +----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ | GRANT USAGE ON *.* TO ‘standby‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*68400CF212112D85B99EB397ADCB27748218BFAE‘ | | GRANT SELECT, UPDATE, DELETE, CREATE, DROP, REFERENCES, INDEX, ALTER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, EVENT, TRIGGER ON `iQiYi`.* TO ‘standby‘@‘localhost‘ | +----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) [email protected] 11:28:29> [email protected] 11:31:50> GRANT INSERT ON `iQiYi`.* to ‘standby‘@‘localhost‘; Query OK, 0 rows affected (0.00 sec) [email protected] 11:32:08> show grants for ‘standby‘@‘localhost‘; +----------------------------------------------------------------------------------------------------------------+ | Grants for [email protected] | +----------------------------------------------------------------------------------------------------------------+ | GRANT USAGE ON *.* TO ‘standby‘@‘localhost‘ IDENTIFIED BY PASSWORD ‘*68400CF212112D85B99EB397ADCB27748218BFAE‘ | | GRANT ALL PRIVILEGES ON `iQiYi`.* TO ‘standby‘@‘localhost‘ | +----------------------------------------------------------------------------------------------------------------+ 2 rows in set (0.00 sec) [email protected] 11:32:10>
mysqldump专业备份命令
时间: 2025-01-02 13:38:21