rpm -qa|grep mariadb

rpm -e --nodeps 文件名

rpm -qa|grep mariadb

wget https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.20-linux-glibc2.12-x86_64.tar.xz

.tar.gz后綴：tar -zxvf 文件名
.tar.xz后綴：tar -Jxvf 文件名

# 重命名
mv 原文件夾名 mysql8
# 軟鏈接
ln -s 文件夾名 mysql8

#臨時(shí)環(huán)境變量，關(guān)閉shell后失效，通常用于測(cè)試環(huán)境
export PATH=$PATH:/data/software/mysql8/bin

# 創(chuàng)建一個(gè)用戶組：mysql
groupadd mysql
# 創(chuàng)建一個(gè)系統(tǒng)用戶：mysql，指定用戶組為mysql
useradd -r -g mysql mysql

mkdir -p /data/software/mysql8/datas

# 更改屬主和數(shù)組
chown -R mysql:mysql /data/software/mysql8/datas
# 更改模式
chmod -R 750 /data/software/mysql8/datas

[mysql]
# 默認(rèn)字符集
default-character-set=utf8mb4
[client]
port       = 3306
socket     = /tmp/mysql.sock

[mysqld]
port       = 3306
server-id  = 3306
user       = mysql
socket     = /tmp/mysql.sock
# 安裝目錄
basedir    = /data/software/mysql8
# 數(shù)據(jù)存放目錄
datadir    = /data/software/mysql8/datas/mysql
log-bin    = /data/software/mysql8/datas/mysql/mysql-bin
innodb_data_home_dir      =/data/software/mysql8/datas/mysql
innodb_log_group_home_dir =/data/software/mysql8/datas/mysql
#日志及進(jìn)程數(shù)據(jù)的存放目錄
log-error =/data/software/mysql8/datas/mysql/mysql.log
pid-file  =/data/software/mysql8/datas/mysql/mysql.pid
# 服務(wù)端使用的字符集默認(rèn)為8比特編碼
character-set-server=utf8mb4
lower_case_table_names=1
autocommit =1
 
 ##################以上要修改的########################
skip-external-locking
key_buffer_size = 256M
max_allowed_packet = 1M
table_open_cache = 1024
sort_buffer_size = 4M
net_buffer_length = 8K
read_buffer_size = 4M
read_rnd_buffer_size = 512K
myisam_sort_buffer_size = 64M
thread_cache_size = 128
  
#query_cache_size = 128M
tmp_table_size = 128M
explicit_defaults_for_timestamp = true
max_connections = 500
max_connect_errors = 100
open_files_limit = 65535
   
binlog_format=mixed
    
binlog_expire_logs_seconds =864000
    
# 創(chuàng)建新表時(shí)將使用的默認(rèn)存儲(chǔ)引擎
default_storage_engine = InnoDB
innodb_data_file_path = ibdata1:10M:autoextend
innodb_buffer_pool_size = 1024M
innodb_log_file_size = 256M
innodb_log_buffer_size = 8M
innodb_flush_log_at_trx_commit = 1
innodb_lock_wait_timeout = 50
transaction-isolation=READ-COMMITTED
      
[mysqldump]
quick
max_allowed_packet = 16M
       
[myisamchk]
key_buffer_size = 256M
sort_buffer_size = 4M
read_buffer = 2M
write_buffer = 2M
        
[mysqlhotcopy]
interactive-timeout

mysqld --defaults-file=/data/software/mysql8/my.cnf --basedir=/data/software/mysql8/ --datadir=/data/software/mysql8/datas/mysql --user=mysql --initialize-insecure

# 完整命令
/data/software/mysql8/bin/mysqld_safe --defaults-file=/data/software/mysql8/my.cnf &
# 添加PATH變量后的命令（省略bin目錄的路徑）
mysqld_safe --defaults-file=/data/software/mysql/my.cnf &

ps -ef|grep mysql

# 無(wú)密碼登錄方式
/data/software/mysql8/bin/mysql -u root --skip-password
# 有密碼登錄方式（初始的隨機(jī)密碼在/data/mysql8_data/mysql/mysql.log下）
mysql -u root -p
password:隨機(jī)密碼

# 修改密碼
ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY '123456';
# 刷新權(quán)限
FLUSH PRIVILEGES;

mysql> use mysql
mysql> update user set user.Host='%'where user.User='root';
mysql> flush privileges;
mysql> quit