Linux_Mysql基础

mysql基础

1. 关系型数据库介绍

1.1 数据结构模型

数据结构模型主要有:

  • 层次模型
  • 网状结构
  • 关系模型

关系模型:
二维关系:row(行,代表一个记录),column(列,代表一个字段)

数据库管理系统:

DBMS(DataBase Management System)

关系型数据库管理系统

RDBMS(Relationship DataBase Management System)

关系:Relational,RDBMS

1.2 RDBMS专业名词

常见的关系型数据库管理系统:

  • MySQL:MySQL,MariaDB,Percona-Server
  • PostgreSQL:简称为pgsql
  • Oracle
  • MSSQL

SQL:Structure Query Language,结构化查询语言

约束:constraint,向数据表提供的数据要遵守的限制

  • 主键约束:一个或多个字段的组合,填入的数据必须能在本表中唯一标识本行。且必须提供数据,不能为空(NOT NULL)。
    • 一个表只能存在一个
  • 惟一键约束:一个或多个字段的组合,填入的数据必须能在本表中唯一标识本行。允许为空(NULL)
    • 一个表可以存在多个
  • 外键约束:一个表中的某字段可填入数据取决于另一个表的主键已有的数据
  • 检查性约束

索引:将表中的一个或多个字段中的数据复制一份另存,并且这些数据需要按特定次序排序存储

1.3 关系型数据库的常见组件

关系型数据库的常见组件有:

  • 数据库:database
  • 表:table,由行(row)和列(column)组成
  • 索引:index
  • 视图:view
  • 用户:user
  • 权限:privilege
  • 存储过程:procedure
  • 存储函数:function
  • 触发器:trigger
  • 事件调度器:event scheduler

1.4 SQL语句

SQL语句有三种类型:

  • DDL:Data Defination Language,数据定义语言
  • DML:Data Manipulation Language,数据操纵语言
  • DCL:Data Control Language,数据控制语言
SQL语句类型 对应操作
DDL CREATE:创建 DROP:删除 ALTER:修改
DML INSERT:向表中插入数据 DELETE:删除表中数据 UPDATE:更新表中数据 SELECT:查询表中数据
DCL GRANT:授权 REVOKE:移除授权

2. mysql安装与配置

2.1 mysql安装

mysql安装方式有三种:

  • 源代码:编译安装
  • 二进制格式的程序包:展开至特定路径,并经过简单配置后即可使用
  • 程序包管理器管理的程序包:
    • rpm:有两种
      • OS Vendor:操作系统发行商提供的
      • 项目官方提供的
    • deb

安装mariadb

[root@localhost ~]# yum -y install mariadb*
Updating Subscription Management repositories.
Unable to read consumer identity
This system is not registered to Red Hat Subscription Management. You can use subscription-manager to register.
Last metadata expiration check: 21:10:39 ago on Mon 21 Dec 2020 06:23:39 AM EST.
Dependencies resolved.
=============================================================================
 Package                      Arch   Version                 Repo       Size
=============================================================================
Installing:
 mariadb                      x86_64 3:10.3.17-1.module+el8.1.0+3974+90eded84
                                                             AppStream 6.1 M
 mariadb-backup               x86_64 3:10.3.17-1.module+el8.1.0+3974+90eded84
                                                             AppStream 6.0 M
 mariadb-common               x86_64 3:10.3.17-1.module+el8.1.0+3974+90eded84
                                                             AppStream  62 k
 mariadb-connector-c          x86_64 3.0.7-1.el8             AppStream 148 k
 mariadb-connector-c-config   noarch 3.0.7-1.el8             AppStream  13 k
 mariadb-connector-c-devel    x86_64 3.0.7-1.el8             AppStream  63 k
 mariadb-connector-odbc       x86_64 3.0.7-1.el8             AppStream 113 k
 mariadb-devel                x86_64 3:10.3.17-1.module+el8.1.0+3974+90eded84
                                                             AppStream 1.0 M
 mariadb-embedded             x86_64 3:10.3.17-1.module+el8.1.0+3974+90eded84
                
  perl-URI-1.73-3.el8.noarch                                                 
  perl-Unicode-Normalize-1.25-396.el8.x86_64                                 
  perl-constant-1.33-396.el8.noarch                                          
                                       

Complete!


2.2 mysql配置

设置开机自动启动,并且现在启动

[root@localhost ~]# systemctl enable --now mariadb
Created symlink /etc/systemd/system/mysql.service → /usr/lib/systemd/system/mariadb.service.
Created symlink /etc/systemd/system/mysqld.service → /usr/lib/systemd/system/mariadb.service.
Created symlink /etc/systemd/system/multi-user.target.wants/mariadb.service → /usr/lib/systemd/system/mariadb.service.
[root@localhost ~]# systemctl status mariadb
● mariadb.service - MariaDB 10.3 database server
   Loaded: loaded (/usr/lib/systemd/system/mariadb.service; enabled; vendor >
   Active: active (running) since Tue 2020-12-22 03:39:18 EST; 10s ago
     Docs: man:mysqld(8)
           https://mariadb.com/kb/en/library/systemd/
  Process: 8402 ExecStartPost=/usr/libexec/mysql-check-upgrade (code=exited,>
  Process: 8267 ExecStartPre=/usr/libexec/mysql-prepare-db-dir mariadb.servi>
  Process: 8243 ExecStartPre=/usr/libexec/mysql-check-socket (code=exited, s>
 Main PID: 8370 (mysqld)
   Status: "Taking your SQL requests now..."
    Tasks: 30 (limit: 4928)
   Memory: 111.2M
   CGroup: /system.slice/mariadb.service
           └─8370 /usr/libexec/mysqld --basedir=/usr

Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: MySQL manu>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: Please rep>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: The latest>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: You can fi>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: http://dev>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: Consider j>
Dec 22 03:39:17 localhost.localdomain mysql-prepare-db-dir[8267]: https://ma>
Dec 22 03:39:17 localhost.localdomain mysqld[8370]: 2020-12-22  3:39:17 0 [N>
Dec 22 03:39:17 localhost.localdomain mysqld[8370]: 2020-12-22  3:39:17 0 [E>
Dec 22 03:39:18 localhost.localdomain systemd[1]: Started MariaDB 10.3 datab>
[root@localhost ~]# ss -antl   //3306端口号已经起来
State    Recv-Q    Send-Q       Local Address:Port       Peer Address:Port   
LISTEN   0         128                0.0.0.0:22              0.0.0.0:*      
LISTEN   0         80                 0.0.0.0:3306            0.0.0.0:*      
LISTEN   0         128                   [::]:22                 [::]:*      
[root@localhost ~]# 

登录mysql

//-u 是指定用户  
[root@localhost ~]# mysql -uroot    //这里的root用户只是数据库的管理员账户
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 9
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> quit
Bye
//-p 需要输入密码登录
[root@localhost ~]# mysql -uroot -p
Enter password: 
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 10
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.
//设置密码
MariaDB [(none)]> set password = password(‘123456‘);   //=后面的password是一个加密函数
Query OK, 0 rows affected (0.001 sec)
//-p后面加密码可以登录(不推荐这种方式登录,容易让别人看见密码)
[root@localhost ~]# mysql -uroot -p123456
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 12
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> quit
Bye
//修改密码
[root@localhost ~]# mysql -uroot -p123456
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 14
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> 
MariaDB [(none)]> alter user root@localhost identified by ‘987654312‘;  //修改密码
Query OK, 0 rows affected (0.001 sec)

MariaDB [(none)]> quit
Bye
[root@localhost ~]# mysql -uroot -p123456   
ERROR 1045 (28000): Access denied for user ‘root‘@‘localhost‘ (using password: YES)
[root@localhost ~]# mysql -uroot -p987654312
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 17
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> quit
Bye


3. mysql的程序组成

  • 客户端
    • mysql:CLI交互式客户端程序
    • mysql_secure_installation:安全初始化,强烈建议安装完以后执行此命令
    • mysqldump:mysql备份工具
    • mysqladmin
  • 服务器端
    • mysqld
[root@localhost ~]# mysql   //tab两下
mysql                       mysql_fix_extensions
mysqlaccess                 mysqlhotcopy
mysqladmin                  mysqlimport
mysqlbinlog                 mysql_install_db
mysqlcheck                  mysql_plugin
mysql_client_test           mysql_secure_installation
mysql_client_test_embedded  mysql_setpermission
mysql_config                mysqlshow
mysql_convert_table_format  mysqlslap
mysqld_multi                mysqltest
mysqld_safe                 mysqltest_embedded
mysqld_safe_helper          mysql_tzinfo_to_sql
mysqldump                   mysql_upgrade
mysqldumpslow               mysql_waitpid
mysql_find_rows  
[root@localhost ~]# ss -antlp
State    Recv-Q    Send-Q       Local Address:Port       Peer Address:Port                                                                                
LISTEN   0         128                0.0.0.0:22              0.0.0.0:*       users:(("sshd",pid=1079,fd=5))                                              
LISTEN   0         80                 0.0.0.0:3306            0.0.0.0:*       users:(("mysqld",pid=8370,fd=21))                                           
LISTEN   0         128                   [::]:22                 [::]:*       users:(("sshd",pid=1079,fd=7))                                              
[root@localhost ~]# 

初始化数据库

[root@localhost ~]# mysql_secure_installation 

NOTE: RUNNING ALL PARTS OF THIS SCRIPT IS RECOMMENDED FOR ALL MariaDB
      SERVERS IN PRODUCTION USE!  PLEASE READ EACH STEP CAREFULLY!

In order to log into MariaDB to secure it, we‘ll need the current
password for the root user.  If you‘ve just installed MariaDB, and
you haven‘t set the root password yet, the password will be blank,
so you should just press enter here.

Enter current password for root (enter for none): 
OK, successfully used password, moving on...

Setting the root password ensures that nobody can log into the MariaDB
root user without the proper authorisation.

You already have a root password set, so you can safely answer ‘n‘.

Change the root password? [Y/n] Y    //是否更改密码
New password: 
Re-enter new password: 
Password updated successfully!
Reloading privilege tables..
 ... Success!


By default, a MariaDB installation has an anonymous user, allowing anyone
to log into MariaDB without having to have a user account created for
them.  This is intended only for testing, and to make the installation
go a bit smoother.  You should remove them before moving into a
production environment.

Remove anonymous users? [Y/n] Y		//是否移除匿名账户
 ... Success!

Normally, root should only be allowed to connect from ‘localhost‘.  This
ensures that someone cannot guess at the root password from the network.

Disallow root login remotely? [Y/n] n		//是否不允许root账户远程登陆
 ... skipping.

By default, MariaDB comes with a database named ‘test‘ that anyone can
access.  This is also intended only for testing, and should be removed
before moving into a production environment.

Remove test database and access to it? [Y/n] Y		//移除测试数据库和他的访问权限
 - Dropping test database...
 ... Success!
 - Removing privileges on test database...
 ... Success!

Reloading the privilege tables will ensure that all changes made so far
will take effect immediately.

Reload privilege tables now? [Y/n] Y		//重新加载权限表
 ... Success!

Cleaning up...

All done!  If you‘ve completed all of the above steps, your MariaDB
installation should now be secure.

Thanks for using MariaDB!

3.1 mysql工具使用

//语法:mysql [OPTIONS] [database]
//常用的OPTIONS:
    -uUSERNAME      //指定用户名,默认为root
    -hHOST          //指定服务器主机,默认为localhost,推荐使用ip地址
    -pPASSWORD      //指定用户的密码
    -P#             //指定数据库监听的端口,这里的#需用实际的端口号代替,如-P3307
    -V              //查看当前使用的mysql版本
    -e          //不登录mysql执行sql语句后退出,常用于脚本

演示如下

[root@localhost ~]# mysql -V
mysql  Ver 15.1 Distrib 10.3.17-MariaDB, for Linux (x86_64) using readline 5.1
[root@localhost ~]# mysql -uroot -p123456
Welcome to the MariaDB monitor.  Commands end with ; or \g.
Your MariaDB connection id is 28
Server version: 10.3.17-MariaDB MariaDB Server

Copyright (c) 2000, 2018, Oracle, MariaDB Corporation Ab and others.

Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
3 rows in set (0.126 sec)

MariaDB [(none)]> quit
Bye
[root@localhost ~]# mysql -uroot -p123456 -e ‘show databases‘  //在外面查看
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
[root@localhost ~]# 

4. mysql数据库操作

4.1 DDL操作

4.1.1 数据库操作

创建数据库

语法:CREATE DATABASE [IF NOT EXISTS] ‘DB_NAME‘;
MariaDB [(none)]> create database school;
Query OK, 1 row affected (0.000 sec)

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| school             |
+--------------------+
4 rows in set (0.001 sec)

MariaDB [(none)]> 

删除数据库

语法:DROP DATABASE [IF EXISTS] ‘DB_NAME‘;
MariaDB [(none)]> drop database school;
Query OK, 0 rows affected (0.311 sec)

MariaDB [(none)]> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
+--------------------+
3 rows in set (0.001 sec)

4.1.2 表操作

创建表

语法:CREATE TABLE table_name (col1 datatype 修饰符,col2 datatype 修饰符) ENGINE=‘存储引擎类型‘;
MariaDB [(none)]> use school;   //进入school数据库
Database changed

MariaDB [school]> CREATE TABLE student(id int not null,name varchar(50) null,age tinyint);      //创建student表
Query OK, 0 rows affected (0.145 sec)

MariaDB [school]> show tables;  //查看已创建的student表
+------------------+
| Tables_in_school |
+------------------+
| student          |
+------------------+
1 row in set (0.002 sec)

MariaDB [school]> DESC student;   //查看student表的结构
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int(11)     | NO   |     | NULL    |       |
| name  | varchar(50) | YES  |     | NULL    |       |
| age   | tinyint(4)  | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
3 rows in set (0.003 sec)

MariaDB [school]> 

添加表里的数据

MariaDB [school]> ALTER TABLE student ADD class varchar(20);
Query OK, 0 rows affected (0.072 sec)
Records: 0  Duplicates: 0  Warnings: 0

MariaDB [school]> DESC student;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int(11)     | NO   |     | NULL    |       |
| name  | varchar(50) | YES  |     | NULL    |       |
| age   | tinyint(4)  | YES  |     | NULL    |       |
| class | varchar(20) | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
4 rows in set (0.002 sec)

MariaDB [school]> 

删除表里的数据

MariaDB [school]> ALTER TABLE student DROP class;
Query OK, 0 rows affected (2.510 sec)
Records: 0  Duplicates: 0  Warnings: 0

MariaDB [school]> DESC student;
+-------+-------------+------+-----+---------+-------+
| Field | Type        | Null | Key | Default | Extra |
+-------+-------------+------+-----+---------+-------+
| id    | int(11)     | NO   |     | NULL    |       |
| name  | varchar(50) | YES  |     | NULL    |       |
| age   | tinyint(4)  | YES  |     | NULL    |       |
+-------+-------------+------+-----+---------+-------+
3 rows in set (0.002 sec)

MariaDB [school]> 

删除表

MariaDB [school]> DROP TABLE student;
Query OK, 0 rows affected (0.032 sec)

MariaDB [school]> show tables;
Empty set (0.001 sec)

MariaDB [school]> 

4.2 查看帮助

//查看创建database的帮助文档
MariaDB [school]> help create database;   
Name: ‘CREATE DATABASE‘
Description:
Syntax:
CREATE {DATABASE | SCHEMA} [IF NOT EXISTS] db_name
    [create_specification] ...

create_specification:
    [DEFAULT] CHARACTER SET [=] charset_name
  | [DEFAULT] COLLATE [=] collation_name

CREATE DATABASE creates a database with the given name. To use this
statement, you need the CREATE privilege for the database. CREATE
SCHEMA is a synonym for CREATE DATABASE.

URL: https://mariadb.com/kb/en/create-database/


MariaDB [school]> 

//查看创建table的帮助文档
MariaDB [school]> help create table;
Name: ‘CREATE TABLE‘
Description:
Syntax:
CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name
    (create_definition,...)
    [table_options]
    [partition_options]

Or:

CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name
    [(create_definition,...)]
    [table_options]
    [partition_options]
    select_statement

Or:

CREATE [TEMPORARY] TABLE [IF NOT EXISTS] tbl_name
    { LIKE old_tbl_name | (LIKE old_tbl_name) }

create_definition:
    col_name column_definition
  | [CONSTRAINT [symbol]] PRIMARY KEY [index_type] (index_col_name,...)
      [index_option] ...
  | {INDEX|KEY} [index_name] [index_type] (index_col_name,...)
      [index_option] ...
  | [CONSTRAINT [symbol]] UNIQUE [INDEX|KEY]
      [index_name] [index_type] (index_col_name,...)
      [index_option] ...
  | {FULLTEXT|SPATIAL} [INDEX|KEY] [index_name] (index_col_name,...)
      [index_option] ...
  | [CONSTRAINT [symbol]] FOREIGN KEY
      [index_name] (index_col_name,...) reference_definition
  | CHECK (expr)

column_definition:
    data_type [NOT NULL | NULL] [DEFAULT default_value]
      [AUTO_INCREMENT] [UNIQUE [KEY] | [PRIMARY] KEY]
      [COMMENT ‘string‘]
      [COLUMN_FORMAT {FIXED|DYNAMIC|DEFAULT}]
      [STORAGE {DISK|MEMORY|DEFAULT}]
      [reference_definition]

data_type:
    BIT[(length)]
  | TINYINT[(length)] [UNSIGNED] [ZEROFILL]
  | SMALLINT[(length)] [UNSIGNED] [ZEROFILL]
  | MEDIUMINT[(length)] [UNSIGNED] [ZEROFILL]
  | INT[(length)] [UNSIGNED] [ZEROFILL]
  | INTEGER[(length)] [UNSIGNED] [ZEROFILL]
  | BIGINT[(length)] [UNSIGNED] [ZEROFILL]
  | REAL[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | DOUBLE[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | FLOAT[(length,decimals)] [UNSIGNED] [ZEROFILL]
  | DECIMAL[(length[,decimals])] [UNSIGNED] [ZEROFILL]
  | NUMERIC[(length[,decimals])] [UNSIGNED] [ZEROFILL]
  | DATE
  | TIME
  | TIMESTAMP
  | DATETIME
  | YEAR
  | CHAR[(length)]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | VARCHAR(length)
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | BINARY[(length)]
  | VARBINARY(length)
  | TINYBLOB
  | BLOB
  | MEDIUMBLOB
  | LONGBLOB
  | TINYTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | TEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | MEDIUMTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | LONGTEXT [BINARY]
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | ENUM(value1,value2,value3,...)
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | SET(value1,value2,value3,...)
      [CHARACTER SET charset_name] [COLLATE collation_name]
  | spatial_type

index_col_name:
    col_name [(length)] [ASC | DESC]

index_type:
    USING {BTREE | HASH}

index_option:
    KEY_BLOCK_SIZE [=] value
  | index_type
  | WITH PARSER parser_name
  | COMMENT ‘string‘

reference_definition:
    REFERENCES tbl_name (index_col_name,...)
      [MATCH FULL | MATCH PARTIAL | MATCH SIMPLE]
      [ON DELETE reference_option]
      [ON UPDATE reference_option]

reference_option:
    RESTRICT | CASCADE | SET NULL | NO ACTION

table_options:
    table_option [[,] table_option] ...

table_option:
    ENGINE [=] engine_name
  | AUTO_INCREMENT [=] value
  | AVG_ROW_LENGTH [=] value
  | [DEFAULT] CHARACTER SET [=] charset_name
  | CHECKSUM [=] {0 | 1}
  | [DEFAULT] COLLATE [=] collation_name
  | COMMENT [=] ‘string‘
  | CONNECTION [=] ‘connect_string‘
  | DATA DIRECTORY [=] ‘absolute path to directory‘
  | DELAY_KEY_WRITE [=] {0 | 1}
  | INDEX DIRECTORY [=] ‘absolute path to directory‘
  | INSERT_METHOD [=] { NO | FIRST | LAST }
  | KEY_BLOCK_SIZE [=] value
  | MAX_ROWS [=] value
  | MIN_ROWS [=] value
  | PACK_KEYS [=] {0 | 1 | DEFAULT}
  | PASSWORD [=] ‘string‘
  | ROW_FORMAT [=] {DEFAULT|DYNAMIC|FIXED|COMPRESSED|REDUNDANT|COMPACT}
  | TABLESPACE tablespace_name [STORAGE {DISK|MEMORY|DEFAULT}]
  | UNION [=] (tbl_name[,tbl_name]...)

partition_options:
    PARTITION BY
        { [LINEAR] HASH(expr)
        | [LINEAR] KEY(column_list)
        | RANGE{(expr) | COLUMNS(column_list)}
        | LIST{(expr) | COLUMNS(column_list)} }
    [PARTITIONS num]
    [SUBPARTITION BY
        { [LINEAR] HASH(expr)
        | [LINEAR] KEY(column_list) }
      [SUBPARTITIONS num]
    ]
    [(partition_definition [, partition_definition] ...)]

partition_definition:
    PARTITION partition_name
        [VALUES 
            {LESS THAN {(expr | value_list) | MAXVALUE} 
            | 
            IN (value_list)}]
        [[STORAGE] ENGINE [=] engine_name]
        [COMMENT [=] ‘comment_text‘ ]
        [DATA DIRECTORY [=] ‘data_dir‘]
        [INDEX DIRECTORY [=] ‘index_dir‘]
        [MAX_ROWS [=] max_number_of_rows]
        [MIN_ROWS [=] min_number_of_rows]
        [TABLESPACE [=] tablespace_name]
        [NODEGROUP [=] node_group_id]
        [(subpartition_definition [, subpartition_definition] ...)]

subpartition_definition:
    SUBPARTITION logical_name
        [[STORAGE] ENGINE [=] engine_name]
        [COMMENT [=] ‘comment_text‘ ]
        [DATA DIRECTORY [=] ‘data_dir‘]
        [INDEX DIRECTORY [=] ‘index_dir‘]
        [MAX_ROWS [=] max_number_of_rows]
        [MIN_ROWS [=] min_number_of_rows]
        [TABLESPACE [=] tablespace_name]
        [NODEGROUP [=] node_group_id]

select_statement:
    [IGNORE | REPLACE] [AS] SELECT ...   (Some valid select statement)

CREATE TABLE creates a table with the given name. You must have the
CREATE privilege for the table.

Rules for permissible table names are given in
https://mariadb.com/kb/en/identifier-names/. By default,
the table is created in the default database, using the InnoDB storage
engine. An error occurs if the table exists, if there is no default
database, or if the database does not exist.

URL: https://mariadb.com/kb/en/create-table/


MariaDB [school]> 


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