Mysql|mariadb

mariadb/mysql数据库

https://dev.mysql.com/downloads/mysql/
https://archive.mariadb.org/ 可以下载二进制
mysql 8–mariadb 10.5以后包含
mysql5.7—mariadb 10.3以前包含
mysql5.6—mariadb 10.1,10.2两个

常见问题

不能启动 mysqld添加innodb_flush_method=normal

优化技巧

1. 表的自增字段支持21亿,bigint更大,溢出会出错
2. 状态,类型,男女尽量使用tinyint smallint,不推荐使用枚举类型
3. IP推荐int 不推荐char(15)
4. 索引不超过5个字段

win初始化

mysql_install_db.exe --datadir=D:\mariadb114\data --password=mysql0

linux ubuntu24.04初始化

 ./mariadb-secure-installation --basedir=/home/mariadb114/  --datadir=/home/mariadb114/data --password=mysql
Disallow root login remotely root远程登陆 n
Remove anonymous users 删除匿名 n
Change the password for root  更改密码n
Remove test database and access to it 删除test y
Reload privilege tables now 重新权限表 y

useradd mysql

./mariadbd  --user=root --basedir=/home/mariadb114/
./mariadbd-safe --user=root --basedir=/home/mariadb114/  --datadir=/home/mariadb114/data

ssh登陆

mysql -u root -h localhost -p
use mysql
update user set host='%' where user='root' and host='localhost';//所有机器可连接
update user set host='106.39.178.131' where user='root' and host='localhost';//指定ip可连接
GRANT ALL PRIVILEGES ON *.* TO '用户'@'%'IDENTIFIED BY '密码' WITH GRANT OPTION; 指定用户可远程连接
flush privileges;

修改默认密码 mysql_secure_installation
sudo vim /etc/mysql/mariadb.conf.d/50-server.cnf
配置文件中的[mysqld]这一块中加入skip-grant-tables
bind-address，把127.0.0.1 改为0.0.0.0
service mysql restart
use mysql;
update user set authentication_string=password("123456") where user="root";
flush privileges;
mysql -u root -p