在Linux中使用MySQL基础SQL语句及校验规则

卸载内置环境

查看是否存在MySQL

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ps axj | grep mysql

关闭MySQL

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systemctl stop mysqld

MySQL对应的安装文件

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rpm -qa | grep mysql

批量卸载

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rpm -qa | grep mysql | xargs yum -y remove

上传MySQL

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rz

查看本地yum源

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ls /etc/yum.repos.d/ -a

安装MySQL

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 rpm -ivh mysql57-community-release-el7.rpm

查看Linux版本

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cat /etc/redhat-release

显示数据库show databases

mysql> show databases;

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

| Database |

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

| information_schema |

| mysql |

| performance_schema |

| sys |

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

4 rows in set (0.02 sec)

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/var/lib/mysql

会多一个目录。

创建

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mysql> create database database1;

删除

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mysql> drop database database1;

数据库的两个编码集

1.数据库编码集数据库未来存储数据

2.数据库校验集支持数据库，进行比较使用的编码，本质也是一种数据库中数据采用的编码方式。

数据库无论是对数据做任何操作，都必须保证操作和编码是一致的。

字符集和校验规则

查看系统默认字符集以及校验规则

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show variables like 'character_set_database';
show variables like 'collation_database';

查看数据库支持的字符集

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show charset;

查看数据库支持的字符集校验规则

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show collation;

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create database d1 charset=utf8 collate utf8_general_ci;

对其进行设置。

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mysql> create database test1 collate utf8_general_ci;

mysql> create database test1 collate utf8_general_ci;

Query OK, 1 row affected, 1 warning (0.02 sec)

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mysql> create database test2 collate utf8_bin;

mysql> create database test2 collate utf8_bin;

Query OK, 1 row affected, 1 warning (0.02 sec)

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mysql> create table person(name varchar(20));

不区分大小写 utf8_general_ci

mysql> select * from person where name='a';
+------+
| name |
+------+
| a |
| A |
+------+

区分大小写 utf8_bin

mysql> use test2

Database changed

mysql> create table person(name varchar(20));

Query OK, 0 rows affected (0.06 sec)

mysql> insert into person (name) values ('a');

Query OK, 1 row affected (0.01 sec)

mysql> insert into person (name) values ('A');

Query OK, 1 row affected (0.02 sec)

mysql> select * from person where name='a';
+------+
| name |
+------+
| a |
+------+

显示

mysql> show tables;

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

| Tables_in_test1 |

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

| person |

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

1 row in set (0.01 sec)

desc

mysql> desc person;

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

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

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

1 row in set (0.01 sec)

select （DQL）

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mysql> select * form person;

插入

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mysql> insert into person (name) values ('D');

order by

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mysql> select * form person order by name;