MySQL 8.0 正式版 8.0.11 已发布，官方表示 MySQL 8 要比 MySQL 5.7 快 2 倍，还带来了大量的改进和更快的性能！
从 MySQL 5.7 升级到 MySQL 8.0 仅支持通过使用 in-place 方式进行升级，并且不支持从 MySQL 8.0 降级到 MySQL 5.7（或从某个 MySQL 8.0 版本降级到任意一个更早的 MySQL 8.0 版本）。唯一受支持的替代方案是在升级之前对数据进行备份。
性能：
MySQL 8.0 的速度要比 MySQL 5.7 快 2 倍。MySQL 8.0 在以下方面带来了更好的性能：读/写工作负载、IO 密集型工作负载、以及高竞争（"hot spot"热点竞争问题）工作负载。
NoSQL
MySQL 从 5.7 版本开始提供 NoSQL 存储功能，目前在 8.0 版本中这部分功能也得到了更大的改进。该项功能消除了对独立的 NoSQL 文档数据库的需求，而 MySQL 文档存储也为 schema-less 模式的 JSON 文档提供了多文档事务支持和完整的 ACID 合规性。
窗口函数(Window Functions)
从 MySQL 8.0 开始，新增了一个叫窗口函数的概念，它可以用来实现若干新的查询方式。窗口函数与 SUM()、COUNT() 这种集合函数类似，但它不会将多行查询结果合并为一行，而是将结果放回多行当中。即窗口函数不需要 GROUP BY
隐藏索引
在 MySQL 8.0 中，索引可以被“隐藏”和“显示”。当对索引进行隐藏时，它不会被查询优化器所使用。我们可以使用这个特性用于性能调试，例如我们先隐藏一个索引，然后观察其对数据库的影响。如果数据库性能有所下降，说明这个索引是有用的，然后将其“恢复显示”即可；如果数据库性能看不出变化，说明这个索引是多余的，可以考虑删掉。
降序索引
MySQL 8.0 为索引提供按降序方式进行排序的支持，在这种索引中的值也会按降序的方式进行排序。
通用表表达式(Common Table Expressions CTE)
在复杂的查询中使用嵌入式表时，使用 CTE 使得查询语句更清晰。
UTF-8 编码
从 MySQL 8 开始，使用 utf8mb4 作为 MySQL 的默认字符集。
JSON
MySQL 8 大幅改进了对 JSON 的支持，添加了基于路径查询参数从 JSON 字段中抽取数据的 JSON_EXTRACT() 函数，以及用于将数据分别组合到 JSON 数组和对象中的 JSON_ARRAYAGG() 和 JSON_OBJECTAGG() 聚合函数。
可靠性
InnoDB 现在支持表 DDL 的原子性，也就是 InnoDB 表上的 DDL 也可以实现事务完整性，要么失败回滚，要么成功提交，不至于出现 DDL 时部分成功的问题，此外还支持 crash-safe 特性，元数据存储在单个事务数据字典中。
高可用性(High Availability)
InnoDB 集群为您的数据库提供集成的原生 HA 解决方案。
对 OpenSSL 的改进、新的默认身份验证、SQL 角色、密码强度、授权。
https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.11-linux-glibc2.12-x86_64.tar
[root@sea_bj_master ~]# cat /etc/redhat-release
CentOS Linux release 7.3.1611 (Core)
[root@sea_bj_master ~]# uname -r
3.10.0-514.21.1.el7.x86_64[root@sea_bj_master ~]# cd /usr/local/src/
[root@sea_bj_master src]# wget https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.11-linux-glibc2.12-x86_64.tar
--2018-06-05 00:19:12-- https://dev.mysql.com/get/Downloads/MySQL-8.0/mysql-8.0.11-linux-glibc2.12-x86_64.tar[root@sea_bj_master src]# useradd -r -s /sbin/nologin -c ‘mysql application run user‘ mysql[root@sea_bj_master src]# tar xf mysql-8.0.11-linux-glibc2.12-x86_64.tar
[root@sea_bj_master src]# ll mysql-*8.0.11-linux-glibc2.12-x86_64.tar*
-rw-r--r-- 1 root root 654131200 Apr 8 14:30 mysql-8.0.11-linux-glibc2.12-x86_64.tar
-rw-r--r-- 1 7161 31415 603019898 Apr 8 16:29 mysql-8.0.11-linux-glibc2.12-x86_64.tar.gz
-rw-r--r-- 1 7161 31415 51099557 Apr 8 16:27 mysql-test-8.0.11-linux-glibc2.12-x86_64.tar.gz
[root@sea_bj_master src]# tar xf mysql-8.0.11-linux-glibc2.12-x86_64.tar.gz
[root@sea_bj_master src]# mv mysql-8.0.11-linux-glibc2.12-x86_64 /usr/local/ -v
‘mysql-8.0.11-linux-glibc2.12-x86_64’ -> ‘/usr/local/mysql-8.0.11-linux-glibc2.12-x86_64’[root@sea_bj_master src]# ln -s /usr/local/mysql-8.0.11-linux-glibc2.12-x86_64 /usr/local/mysql -v
‘/usr/local/mysql’ -> ‘/usr/local/mysql-8.0.11-linux-glibc2.12-x86_64’[root@sea_bj_master src]# mkdir -v /usr/local/mysql/mysql-files
mkdir: created directory ‘/usr/local/mysql/mysql-files’[root@sea_bj_master src]# mkdir /application/mysql/data -v
mkdir: created directory ‘/application/mysql/data’[root@sea_bj_master src]# chown root.mysql -R /usr/local/mysql-8.0.11-linux-glibc2.12-x86_64[root@sea_bj_master src]# chown mysql.mysql -R /application/mysql/data /usr/local/mysql/mysql-files -v
ownership of ‘/application/mysql/data’ retained as mysql:mysql
ownership of ‘/usr/local/mysql/mysql-files’ retained as mysql:mysql[root@sea_bj_master src]# mv /etc/my.cnf{,.old} -v
mv: overwrite ‘/etc/my.cnf.old’? y
‘/etc/my.cnf’ -> ‘/etc/my.cnf.old’[root@sea_bj_master src]# /usr/local/mysql/bin/mysqld --initialize --user=mysql --datadir=/application/mysql/data --basedir=/usr/local/mysql
2018-06-04T16:32:33.389541Z 0 [System] [MY-013169] [Server] /usr/local/mysql/bin/mysqld (mysqld 8.0.11) initializing of server in progress as process 681
2018-06-04T16:32:39.406682Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: mD4Tbl#0d8:W
2018-06-04T16:32:42.307915Z 0 [System] [MY-013170] [Server] /usr/local/mysql/bin/mysqld (mysqld 8.0.11) initializing of server has completed[root@sea_bj_master src]# /usr/local/mysql/bin/mysql_ssl_rsa_setup --user=mysql --datadir=/application/mysql/data --basedir=/usr/local/mysql[root@sea_bj_master src]# cat /usr/lib/systemd/system/mysqld.service
#
# Simple MySQL systemd service file
#
# systemd supports lots of fancy features, look here (and linked docs) for a full list:
# http://www.freedesktop.org/software/systemd/man/systemd.exec.html
#
# Note: this file ( /usr/lib/systemd/system/mysql.service )
# will be overwritten on package upgrade, please copy the file to
#
# /etc/systemd/system/mysql.service
#
# to make needed changes.
#
# systemd-delta can be used to check differences between the two mysql.service files.
#
[Unit]
Description=MySQL Community Server
After=network.target
After=syslog.target
[Install]
WantedBy=multi-user.target
Alias=mysql.service
[Service]
User=mysql
Group=mysql
# Execute pre and post scripts as root
PermissionsStartOnly=true
# Needed to create system tables etc.
#ExecStartPre=/usr/bin/mysql-systemd-start pre
# Start main service
ExecStart=/usr/local/mysql/bin/mysqld_safe
# Don‘t signal startup success before a ping works
#ExecStartPost=/usr/bin/mysql-systemd-start post
# Give up if ping don‘t get an answer
TimeoutSec=600
Restart=always
PrivateTmp=false[root@sea_bj_master src]# systemctl daemon-reload[root@sea_bj_master src]# cat /etc/my.cnf
[mysqld]
user = mysql
bind_address = 0.0.0.0
character_set_server=utf8mb4
skip_name_resolve = 1
max_connections = 800
max_connect_errors = 1000
datadir = /application/mysql/data[root@sea_bj_master src]# systemctl start mysqld
[root@sea_bj_master src]# systemctl status mysqld
● mysqld.service - MySQL Community Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; disabled; vendor preset: disabled)
Active: active (running) since Tue 2018-06-05 00:42:23 CST; 5s ago
Main PID: 2273 (mysqld_safe)
CGroup: /system.slice/mysqld.service
├─2273 /bin/sh /usr/local/mysql/bin/mysqld_safe
└─2424 /usr/local/mysql/bin/mysqld --basedir=/usr/local/mysql --datadir=/application/mysql/data --plugin...
Jun 05 00:42:23 sea_bj_master systemd[1]: Started MySQL Community Server.
Jun 05 00:42:23 sea_bj_master systemd[1]: Starting MySQL Community Server...
Jun 05 00:42:23 sea_bj_master mysqld_safe[2273]: 2018-06-04T16:42:23.125697Z mysqld_safe Logging to ‘/applicati...rr‘.
Jun 05 00:42:23 sea_bj_master mysqld_safe[2273]: 2018-06-04T16:42:23.144258Z mysqld_safe Starting mysqld daemon...data
Hint: Some lines were ellipsized, use -l to show in full.[root@sea_bj_master src]# mysql -p‘mD4Tbl#0d8:W‘
mysql: [Warning] Using a password on the command line interface can be insecure.
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.11
Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.
Type ‘help;‘ or ‘\h‘ for help. Type ‘\c‘ to clear the current input statement.
mysql> set password = ‘123‘;
Query OK, 0 rows affected (0.04 sec)
mysql> \s
--------------
mysql Ver 8.0.11 for linux-glibc2.12 on x86_64 (MySQL Community Server - GPL)
Connection id: 8
Current database:
Current user: root@localhost
SSL: Not in use
Current pager: stdout
Using outfile: ‘‘
Using delimiter: ;
Server version: 8.0.11
Protocol version: 10
Connection: Localhost via UNIX socket
Server characterset: utf8mb4
Db characterset: utf8mb4
Client characterset: utf8mb4
Conn. characterset: utf8mb4
UNIX socket: /tmp/mysql.sock
Uptime: 1 min 0 sec
Threads: 2 Questions: 7 Slow queries: 0 Opens: 238 Flush tables: 2 Open tables: 73 Queries per second avg: 0.116
--------------原文地址：http://blog.51cto.com/lisea/2124845
