Centos7安装MySQL8.0 – 操作手册

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MySQL 8 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！

一.  Mysql8.0版本相比之前版本的一些特性

1) 默认编码utf8
默认编码使用utf8mb4, utf8mb4编码是utf8编码的超集，兼容utf8，并且能存储4字节的表情字符历史，MySQL数据库的 "utf8"并不是真正概念里的 UTF-8。MySQL中的"utf8"编码只支持最大3字节每字符。真正的大家正在使用的UTF-8编码是应该能支持4字节每个字符。MySQL的开发者没有修复这个bug。他们在2010年增加了一个变通的方法：一个新的字符集"utf8mb4"另外，utf-32编码固定使用4字节，32bit存储相比utf8浪费空间。

2) 降序索引
在之前的版本中可以创建，但是实际创建的还是升序索引

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mysql> create table t1(id1 int,id2 int,key(id1,id2 desc));
Query OK, 0 rows affected (0.10 sec)
 
mysql> show create table t1 \G;
*************************** 1. row ***************************
       Table: t1
Create Table: CREATE TABLE `t1` (
  `id1` int(11) DEFAULT NULL,
  `id2` int(11) DEFAULT NULL,
  KEY `id1` (`id1`,`id2` DESC)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_0900_ai_ci
1 row in set (0.00 sec)
 
ERROR:
No query specified

另外，由于降序索引的引入，MySQL 8.0再也不会对group by操作进行隐式排序

3) 隐藏索引
隐藏索引的特性对于性能调试非常有用。当一个索引隐藏时，它不会被查询优化器所使用。也就是说，我们可以隐藏一个索引，然后观察对数据库的影响。如果数据库性能有所下降，就说明这个索引是有用的，于是将其“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，可以删掉了.

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mysql> create index idx2 on t1(id1);
Query OK, 0 rows affected (0.35 sec)
Records: 0  Duplicates: 0  Warnings: 0
 
mysql> alter table t1 alter index idx2 invisible;
Query OK, 0 rows affected (0.09 sec)
Records: 0  Duplicates: 0  Warnings: 0
 
mysql> show index from t1 where key_name='idx2' \G;
*************************** 1. row ***************************
        Table: t1
   Non_unique: 1
     Key_name: idx2
 Seq_in_index: 1
  Column_name: id1
    Collation: A
  Cardinality: 0
     Sub_part: NULL
       Packed: NULL
         Null: YES
   Index_type: BTREE
      Comment:
Index_comment:
      Visible: NO
1 row in set (0.01 sec)
 
ERROR:
No query specified

当索引被隐藏时，它的内容仍然是和正常索引一样实时更新的，此特性是专门为优化调试使用。如果长期隐藏一个索引，那还不如干脆删掉，因为毕竟索引存在会影响插入、更新和删除的性能.

4) 设置持久化
在oracle中可以使用scope设置参数确定是否到spfile, 现在mysql8.0也可以放在文件中了，使用方法:

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mysql> show variables like 'max_connects';
Empty set (0.07 sec)
 
mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 500   |
+-----------------+-------+
1 row in set (0.01 sec)
 
mysql> set persist max_connections=1000;
Query OK, 0 rows affected (0.00 sec)
 
mysql> show variables like 'max_connections';
+-----------------+-------+
| Variable_name   | Value |
+-----------------+-------+
| max_connections | 1000  |
+-----------------+-------+
1 row in set (0.01 sec)

可以查看在数据目录datadir中的一个mysqld-auto.cnf文件中保存了设置，下次启动时候将用此配置覆盖默认配置参数
{ "Version" : 1 , "mysql_server" : { "max_connections" : { "Value" : "1000" , "Metadata" : { "Timestamp" : 1540437420567571 , "User" : "root" , "Host" : "" } } } }

5) 通用表表达式（Common Table Expressions）
也可以称为虚拟视图，大大简化复杂查询

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mysql> WITH
    ->  t1 AS (SELECT * FROM t1),
    ->  t2 AS (SELECT * FROM t1)
    -> SELECT t1.*, t2.*
    -> FROM t1, t2;
+------+------+------+------+
| id1  | id2  | id1  | id2  |
+------+------+------+------+
|    1 |    2 |    1 |    2 |
+------+------+------+------+
1 row in set (0.00 sec)

6) 窗口函数（Window Functions）
MySQL 被吐槽最多的特性之一就是缺少 rank() 函数，当需要在查询当中实现排名时，必须手写 @ 变量。但是从 8.0 开始，MySQL 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
说明，窗口可以单独创建。

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mysql> create table tbl2(name varchar(10),amount int);
Query OK, 0 rows affected (0.16 sec)
 
mysql> insert into tbl2 values('usa',100),('china',101),('japan',103),('russian',99);
Query OK, 4 rows affected (0.13 sec)
Records: 4  Duplicates: 0  Warnings: 0
 
mysql> select t1.*,rank() over w as 'rank' from tbl2 as t1 window w as (order by amount);
+---------+--------+------+
| name    | amount | rank |
+---------+--------+------+
| russian |     99 |    1 |
| usa     |    100 |    2 |
| china   |    101 |    3 |
| japan   |    103 |    4 |
+---------+--------+------+
4 rows in set (0.00 sec)
 
mysql> select t1.*,rank() over() as 'rank' from tbl2 as t1;
+---------+--------+------+
| name    | amount | rank |
+---------+--------+------+
| usa     |    100 |    1 |
| china   |    101 |    1 |
| japan   |    103 |    1 |
| russian |     99 |    1 |
+---------+--------+------+
4 rows in set (0.00 sec)
 
mysql> select t1.*,rank() over(order by amount) as 'rank' from tbl2 as t1;
+---------+--------+------+
| name    | amount | rank |
+---------+--------+------+
| russian |     99 |    1 |
| usa     |    100 |    2 |
| china   |    101 |    3 |
| japan   |    103 |    4 |
+---------+--------+------+
4 rows in set (0.00 sec)
 
mysql> select t1.*,sum() over() as 'rank' from tbl2 as t1;
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ') over() as 'rank' from tbl2 as t1' at line 1
mysql> select t1.*,sum(amount) over() as 'sum' from tbl2 as t1;
+---------+--------+------+
| name    | amount | sum  |
+---------+--------+------+
| usa     |    100 |  403 |
| china   |    101 |  403 |
| japan   |    103 |  403 |
| russian |     99 |  403 |
+---------+--------+------+
4 rows in set (0.00 sec)

7) 安全性
对 OpenSSL 的改进、新的默认身份验证、SQL 角色、密码强度、授权。MySQL现在维护关于密码历史的信息，允许对以前密码的重用进行限制
比如常见的一个连接错误，参考：https://blog.csdn.net/jc_benben/article/details/80652897

8) 增加JSON （json enhancements）AND OpenGIS spatial types
mysql提供了很多json相关的函数和API接口，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

9) 原子数据定义语句（原子DDL）（Atomic Data Definition Statements (Atomic DDL)）

10) 资源管理（Resource management）
MySQL现在支持资源组的创建和管理，并允许将服务器内运行的线程分配给特定组，以便线程根据组可用的资源执行。组属性可以控制其资源，以启用或限制组中线程的资源消耗

11) Data dictionary
MySQL现在包含一个事务数据字典，用于存储有关数据库对象的信息，In previous MySQL releases, dictionary data was stored in metadata files and nontransactional tables
比如myisam和innodb表定义frm文件等.

12) innodb的增强
1  每次值更改时，当前最大自动增量计数器值将写入重做日志，并保存到每个检查点上的引擎专用系统表中。这些更改使当前最大自动增量计数器值在服务器重新启动时保持不变。
2 遇到索引树损坏时， InnoDB将损坏标志写入重做日志，这会使损坏标志崩溃安全。InnoDB还将内存中损坏标志数据写入每个检查点上的引擎专用系统表。在恢复期间， InnoDB从两个位置读取损坏标志并在将内存表和索引对象标记为损坏之前合并结果。
3 InnoDB 分布式缓存插件支持多个get操作（读取在一个单一的多键/值对分布式缓存查询）和范围查询;
4 新的动态配置选项 innodb_deadlock_detect可用于禁用死锁检测。在高并发系统上，当许多线程等待同一个锁时，死锁检测会导致速度减慢。有时，禁用死锁检测可能更有效，并且在innodb_lock_wait_timeout发生死锁时依赖于事务回滚的设置。
5 INFORMATION_SCHEMA.INNODB_CACHED_INDEXES 表报告InnoDB每个索引缓冲池中缓存的索引页数 。
6 InnoDB现在，在共享临时表空间中创建临时表ibtmp1。
7 InnoDB 表空间加密功能支持重做日志的加密和撤消日志数据;
8 InnoDB支持 NOWAIT和SKIP LOCKED选项SELECT ... FOR SHARE以及SELECT ... FOR UPDATE锁定读取语句。 NOWAIT如果请求的行被另一个事务锁定，则会立即返回该语句。SKIP LOCKED从结果集中删除锁定的行SELECT ... FOR SHARE替换 SELECT ... LOCK IN SHARE MODE，但LOCK IN SHARE MODE仍可用于向后兼容;
9 支持ADD PARTITION，DROP PARTITION，COALESCE PARTITION，REORGANIZE PARTITION，和REBUILD PARTITION ALTER TABLE选项;
10 InnoDB存储引擎现在使用MySQL的数据字典，而不是它自己的存储引擎特定的数据字典;
11 mysql系统表和数据字典表现在在MySQL数据目录中InnoDB命名的单个表空间文件创建mysql.ibd。以前，这些表是InnoDB在mysql数据库目录中的各个表空间文件中创建的;

二.  Mysql8.0安装 (YUM方式)

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1) 首先删除系统默认或之前可能安装的其他版本的mysql
[root@DB-node01 ~]# for i in $(rpm -qa|grep mysql);do rpm -e $i --nodeps;done
[root@DB-node01 ~]# rm -rf /var/lib/mysql && rm -rf /etc/my.cnf
  
2) 安装Mysql8.0 的yum资源库
mysql80-community-release-el7-1.noarch.rpm    下载地址:  https://pan.baidu.com/s/1QzYaSnzAQeTqAmk8FE9doA
提取密码: 2maw
[root@DB-node01 ~]# yum localinstall https://repo.mysql.com//mysql80-community-release-el7-1.noarch.rpm
  
3) 安装Mysql8.0
[root@DB-node01 ~]# yum install mysql-community-server
  
启动MySQL服务器和MySQL的自动启动
[root@DB-node01 ~]# systemctl start mysqld
[root@DB-node01 ~]# systemctl enable mysqld
  
4) 使用默认密码初次登录后, 必须要重置密码
  
查看默认密码, 如下默认密码为"e53xDalx.*dE"
[root@DB-node01 ~]# grep 'temporary password' /var/log/mysqld.log
2019-03-06T01:53:19.897262Z 5 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: e53xDalx.*dE
  
[root@DB-node01 ~]# mysql -pe53xDalx.*dE
............
mysql> select version();
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
  
报错提示必须要重置初始密码, 下面开始重置mysql登录密码（注意要切换到mysql数据库，使用use mysql）
mysql> use mysql;
ERROR 1820 (HY000): You must reset your password using ALTER USER statement before executing this statement.
  
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
ERROR 1819 (HY000): Your password does not satisfy the current policy requirements
  
这个其实与validate_password_policy的值有关, mysql8.0更改了validate_password_policy相关的配置名称, 这跟Mysql5.7有点不一样了.
mysql> set global validate_password.policy=0;
Query OK, 0 rows affected (0.00 sec)
  
mysql> set global validate_password.length=1;
Query OK, 0 rows affected (0.00 sec)
  
接着再修改密码
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.05 sec)
  
mysql> flush privileges;
Query OK, 0 rows affected (0.03 sec)
  
退出, 重新使用新密码登录mysql
[root@DB-node01 ~]# mysql -p123456
...........
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.15    |
+-----------+
1 row in set (0.00 sec)
  
查看服务端口
mysql> show global variables like 'port';
+---------------+-------+
| Variable_name | Value |
+---------------+-------+
| port          | 3306  |
+---------------+-------+
1 row in set (0.01 sec)
  
查看mysql连接的授权信息
mysql> select host,user,password from mysql.user;
ERROR 1054 (42S22): Unknown column 'password' in 'field list'
  
上面这是mysql5.6及以下版本的查看命令,
mysql5.7之后的数据库里mysql.user表里已经没有password这个字段了，password字段改成了authentication_string。
mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root             | $A$005${7J0=4Dc7Jym8eI/FU4jimKWFvkD9XmoAkF1ca5.Un0bc6zgmPtU.0          |
+-----------+------------------+------------------------------------------------------------------------+
4 rows in set (0.00 sec)
  
=============================mysql8.0修改用户密码命令================================
mysql> use mysql;
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
mysql> flush privileges;

三.  Mysql8.0安装 (二进制方式)

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1) 首先删除系统默认或之前可能安装的其他版本的mysql
[root@mysql8-node ~]# for i in $(rpm -qa|grep mysql);do rpm -e $i --nodeps;done
[root@mysql8-node ~]# rm -rf /var/lib/mysql && rm -rf /etc/my.cnf
2) 安装需要的软件包
[root@mysql8-node ~]# yum -y install libaio
[root@mysql8-node ~]# yum -y install net-tools
3) 下载并安装Mysql8.0.12
下载地址:  https://pan.baidu.com/s/1LyXrkrCPP7QKLrWYbLRBlw
提取密码:  emmf
[root@mysql8-node ~]# groupadd mysql
[root@mysql8-node ~]# useradd -g mysql mysql
[root@mysql8-node ~]# cd /usr/local/src/
[root@mysql-node src]# ll
-rw-r--r-- 1 root root 620389228 Aug 22  2018 mysql8.0.12_bin_centos7.tar.gz
[root@mysql-node src]# tar -zvxf mysql8.0.12_bin_centos7.tar.gz
[root@mysql-node src]# mv mysql /usr/local/
[root@mysql-node src]# chown -R mysql.mysql /usr/local/mysql
[root@mysql-node src]# vim /home/mysql/.bash_profile
export PATH=/usr/local/mysql/bin:/usr/local/mysql/lib:$PATH
[root@mysql-node src]# source /home/mysql/.bash_profile
[root@mysql-node src]# echo "PATH=$PATH:/usr/local/mysql/bin" >> /etc/profile
[root@mysql-node src]# source /etc/profile
4) 创建数据目录
[root@mysql-node src]# mkdir -p /data/mysql/{data,log,binlog,conf,tmp}         
[root@mysql-node src]# chown -R mysql.mysql /data/mysql
5) 配置mysql
[root@mysql-node src]# su - mysql
[mysql@mysql-node ~]$ vim /data/mysql/conf/my.cnf
[mysqld]
lower_case_table_names          = 1
user                            = mysql
server_id                       = 1
port                            = 3306
default-time-zone = '+08:00'
enforce_gtid_consistency        = ON
gtid_mode                       = ON
binlog_checksum                 = none
default_authentication_plugin   = mysql_native_password
datadir                         = /data/mysql/data
pid-file                        = /data/mysql/tmp/mysqld.pid
socket                          = /data/mysql/tmp/mysqld.sock
tmpdir                          = /data/mysql/tmp/
skip-name-resolve               = ON
open_files_limit                = 65535
table_open_cache                = 2000
#################innodb########################
innodb_data_home_dir            = /data/mysql/data
innodb_data_file_path           = ibdata1:512M;ibdata2:512M:autoextend
innodb_buffer_pool_size = 12000M
innodb_flush_log_at_trx_commit = 1
innodb_io_capacity = 600
innodb_lock_wait_timeout = 120
innodb_log_buffer_size = 8M
innodb_log_file_size = 200M
innodb_log_files_in_group = 3
innodb_max_dirty_pages_pct = 85
innodb_read_io_threads = 8
innodb_write_io_threads = 8
innodb_thread_concurrency = 32
innodb_file_per_table
innodb_rollback_on_timeout
innodb_undo_directory           = /data/mysql/data
innodb_log_group_home_dir       = /data/mysql/data
###################session###########################
join_buffer_size = 8M
key_buffer_size = 256M
bulk_insert_buffer_size = 8M
max_heap_table_size = 96M
tmp_table_size = 96M
read_buffer_size = 8M
sort_buffer_size = 2M
max_allowed_packet = 64M
read_rnd_buffer_size = 32M
############log set###################
log-error                       = /data/mysql/log/mysqld.err
log-bin                         = /data/mysql/binlog/binlog
log_bin_index                   = /data/mysql/binlog/binlog.index
max_binlog_size                 = 500M
slow_query_log_file             = /data/mysql/log/slow.log
slow_query_log                  = 1
long_query_time                 = 10
log_queries_not_using_indexes   = ON
log_throttle_queries_not_using_indexes  = 10
log_slow_admin_statements       = ON
log_output                      = FILE,TABLE
master_info_file                = /data/mysql/binlog/master.info
6) 初始化 (稍等一会儿, 可以到/data/mysql/log/mysqld.err日子里查看初始化过程, 看看有没有error信息)
[mysql@mysql-node ~]$ mysqld --defaults-file=/data/mysql/conf/my.cnf  --initialize-insecure  --user=mysql 
7) 启动mysqld
[mysql@mysql-node ~]$ mysqld_safe --defaults-file=/data/mysql/conf/my.cnf & 
[mysql@mysql-node ~]$ lsof -i:3306
COMMAND   PID  USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
mysqld  24743 mysql   23u  IPv6 23132988      0t0  TCP *:mysql (LISTEN)
8) 登录mysql, 重置密码
本地首次使用sock文件登录mysql是不需要密码的
[mysql@mysql-node ~]# mysql -S /data/mysql/tmp/mysqld.sock
.............
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.07 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.03 sec)
mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root             | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
+-----------+------------------+------------------------------------------------------------------------+
4 rows in set (0.00 sec)
退出, 此时密码重置后, 就不能使用sock文件无密码登录了
[root@mysql-node ~]# mysql -S /data/mysql/tmp/mysqld.sock
ERROR 1045 (28000): Access denied for user 'root'@'localhost' (using password: NO)
[root@mysql-node ~]# mysql -p123456
mysql: [Warning] Using a password on the command line interface can be insecure.
ERROR 2002 (HY000): Can't connect to local MySQL server through socket '/tmp/mysql.sock' (2)
做sock文件的软链接
[root@mysql-node ~]# ln -s /data/mysql/tmp/mysqld.sock /tmp/mysql.sock
[root@mysql-node ~]# mysql -p123456
或者
[root@mysql-node ~]# mysql -uroot -S /data/mysql/tmp/mysqld.sock -p123456
.............
mysql> select version();
+-----------+
| version() |
+-----------+
| 8.0.12    |
+-----------+
1 row in set (0.00 sec)
#授予用户权限. 必须先要创建用户, 才能授权!!
(创建用户时要带@并指定地址, 则grant授权时的地址就是这个@后面指定的!, 否则grant授权就会报错!)
mysql> create user 'kevin'@'%' identified by '123456';
Query OK, 0 rows affected (0.11 sec)
mysql> grant all privileges on *.* to 'kevin'@'%' with grant option; 
Query OK, 0 rows affected (0.21 sec)
mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| %         | kevin            | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root             | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
+-----------+------------------+------------------------------------------------------------------------+
5 rows in set (0.00 sec)
mysql> update mysql.user set host='172.16.60.%' where user="kevin";
Query OK, 1 row affected (0.16 sec)
Rows matched: 1  Changed: 1  Warnings: 0
mysql> flush privileges;
Query OK, 0 rows affected (0.05 sec)
mysql> select host,user,authentication_string from mysql.user;
+-------------+------------------+------------------------------------------------------------------------+
| host        | user             | authentication_string                                                  |
+-------------+------------------+------------------------------------------------------------------------+
| 172.16.60.% | kevin            | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
| localhost   | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | root             | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
+-------------+------------------+------------------------------------------------------------------------+
5 rows in set (0.00 sec)
mysql>  create user 'bobo'@'172.16.60.%' identified by '123456';      
Query OK, 0 rows affected (0.09 sec)
mysql> grant all privileges on *.* to 'bobo'@'172.16.60.%';     
Query OK, 0 rows affected (0.17 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.04 sec)
mysql> select host,user,authentication_string from mysql.user;
+-------------+------------------+------------------------------------------------------------------------+
| host        | user             | authentication_string                                                  |
+-------------+------------------+------------------------------------------------------------------------+
| 172.16.60.% | bobo             | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
| 172.16.60.% | kevin            | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
| localhost   | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost   | root             | *6BB4837EB74329105EE4568DDA7DC67ED2CA2AD9                              |
+-------------+------------------+------------------------------------------------------------------------+
6 rows in set (0.00 sec)
mysql> show grants for kevin@'172.16.60.%';
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Grants for kevin@172.16.60.%                                                                                                                                                                                                                                                                                                                                                                                |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| GRANT SELECT, INSERT, UPDATE, DELETE, CREATE, DROP, RELOAD, SHUTDOWN, PROCESS, FILE, REFERENCES, INDEX, ALTER, SHOW DATABASES, SUPER, CREATE TEMPORARY TABLES, LOCK TABLES, EXECUTE, REPLICATION SLAVE, REPLICATION CLIENT, CREATE VIEW, SHOW VIEW, CREATE ROUTINE, ALTER ROUTINE, CREATE USER, EVENT, TRIGGER, CREATE TABLESPACE, CREATE ROLE, DROP ROLE ON *.* TO `kevin`@`172.16.60.%` WITH GRANT OPTION |
+-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
1 row in set (0.00 sec)

MySQL单机多实例安装配置
通过上面二进制部署可知, 已经起来一个3306端口的MySQL实例, 现在需要再起来两个实例, 分别为3307, 3308. 操作如下:

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创建实例的数据目录
[root@mysql-node ~]# mkdir -p /data/mysql3307/{data,log,binlog,conf,tmp}      
[root@mysql-node ~]# mkdir -p /data/mysql3308/{data,log,binlog,conf,tmp}     
[root@mysql-node ~]# chown -R mysql.mysql /data/mysql3307
[root@mysql-node ~]# chown -R mysql.mysql /data/mysql3308
配置mysql
[root@mysql-node ~]# cp -r /data/mysql/conf/my.cnf /data/mysql3307/conf/
[root@mysql-node ~]# cp -r /data/mysql/conf/my.cnf /data/mysql3308/conf/
[root@mysql-node ~]# sed -i 's#/data/mysql/#/data/mysql3307/#g' /data/mysql3307/conf/my.cnf
[root@mysql-node ~]# sed -i 's#/data/mysql/#/data/mysql3308/#g' /data/mysql3308/conf/my.cnf
[root@mysql-node ~]# sed -i 's/3306/3307/g' /data/mysql3307/conf/my.cnf
[root@mysql-node ~]# sed -i 's/3306/3308/g' /data/mysql3308/conf/my.cnf  
[root@mysql-node ~]# chown -R mysql.mysql /data/mysql*
进行初始化两个实例
[root@mysql-node ~]# mysqld --defaults-file=/data/mysql3307/conf/my.cnf  --initialize-insecure  --user=mysql 
[root@mysql-node ~]# mysqld --defaults-file=/data/mysql3308/conf/my.cnf  --initialize-insecure  --user=mysql
接着启动mysqld
[root@mysql-node ~]# mysqld_safe --defaults-file=/data/mysql3307/conf/my.cnf &
[root@mysql-node ~]# mysqld_safe --defaults-file=/data/mysql3308/conf/my.cnf &
[root@mysql-node ~]# ps -ef|grep mysql
mysql    23996     1  0 14:37 ?        00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --defaults-file=/data/mysql/conf/my.cnf
mysql    24743 23996  0 14:38 ?        00:00:17 /usr/local/mysql/bin/mysqld --defaults-file=/data/mysql/conf/my.cnf --basedir=/usr/local/mysql --datadir=/data/mysql/data --plugin-dir=/usr/local/mysql/lib/plugin --log-error=/data/mysql/log/mysqld.err --open-files-limit=65535 --pid-file=/data/mysql/tmp/mysqld.pid --socket=/data/mysql/tmp/mysqld.sock --port=3306
root     30473 23727  0 15:33 pts/0    00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --defaults-file=/data/mysql3307/conf/my.cnf
mysql    31191 30473 17 15:33 pts/0    00:00:02 /usr/local/mysql/bin/mysqld --defaults-file=/data/mysql3307/conf/my.cnf --basedir=/usr/local/mysql --datadir=/data/mysql3307/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/data/mysql3307/log/mysqld.err --open-files-limit=65535 --pid-file=/data/mysql3307/tmp/mysqld.pid --socket=/data/mysql3307/tmp/mysqld.sock --port=3307
root     31254 23727  0 15:33 pts/0    00:00:00 /bin/sh /usr/local/mysql/bin/mysqld_safe --defaults-file=/data/mysql3308/conf/my.cnf
mysql    31977 31254 39 15:33 pts/0    00:00:02 /usr/local/mysql/bin/mysqld --defaults-file=/data/mysql3308/conf/my.cnf --basedir=/usr/local/mysql --datadir=/data/mysql3308/data --plugin-dir=/usr/local/mysql/lib/plugin --user=mysql --log-error=/data/mysql3308/log/mysqld.err --open-files-limit=65535 --pid-file=/data/mysql3308/tmp/mysqld.pid --socket=/data/mysql3308/tmp/mysqld.sock --port=3308
root     32044 23727  0 15:34 pts/0    00:00:00 grep --color=auto mysql
[root@mysql-node ~]# lsof -i:3307
COMMAND   PID  USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
mysqld  31191 mysql   22u  IPv6 23144844      0t0  TCP *:opsession-prxy (LISTEN)
[root@mysql-node ~]# lsof -i:3308
COMMAND   PID  USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
mysqld  31977 mysql   22u  IPv6 23145727      0t0  TCP *:tns-server (LISTEN)
[root@mysql-node ~]# lsof -i:3306
COMMAND   PID  USER   FD   TYPE   DEVICE SIZE/OFF NODE NAME
mysqld  24743 mysql   23u  IPv6 23132988      0t0  TCP *:mysql (LISTEN)
登录3307端口实例, 并设置密码
[root@mysql-node ~]# mysql -S /data/mysql3307/tmp/mysqld.sock
............
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.11 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.11 sec)
退出, 使用新密码登录
[root@mysql-node ~]# mysql -uroot -S /data/mysql3307/tmp/mysqld.sock -p123456   
.............
mysql>
同理, 登录3308端口实例, 并设置密码
[root@mysql-node ~]# mysql -S /data/mysql3308/tmp/mysqld.sock
...........
mysql> ALTER USER 'root'@'localhost' IDENTIFIED BY '123456';
Query OK, 0 rows affected (0.13 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.03 sec)
退出, 使用新密码登录
[root@mysql-node ~]# mysql -uroot -S /data/mysql3308/tmp/mysqld.sock -p123456
....................
mysql>
==========================================
3306, 3307, 3308三个端口实例的启动命令分别为:
mysqld_safe --defaults-file=/data/mysql/conf/my.cnf &
mysqld_safe --defaults-file=/data/mysql3307/conf/my.cnf &
mysqld_safe --defaults-file=/data/mysql3308/conf/my.cnf &
登录命令分别为:
mysql -uroot -S /data/mysql/tmp/mysqld.sock -p123456
mysql -uroot -S /data/mysql3307/tmp/mysqld.sock -p123456
mysql -uroot -S /data/mysql3308/tmp/mysqld.sock -p123456

 编写mysql多端口实例的登录脚本 

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上面的多端口实例配置之后, 查看一个登录脚本:myin (注意将脚本中的密码改为自己的密码)
[root@mysql-node ~]# ll /usr/local/mysql/bin/myin
-rwxrwxr-x 1 mysql mysql 161 Aug 22  2018 /usr/local/mysql/bin/myin
[root@mysql-node ~]# cat /usr/local/mysql/bin/myin
#!/bin/bash
p=$1
shift
mysql -h"127.0.0.1" -P"$p" --default-character-set=utf8mb4 --show-warnings -uroot -p'123456' -A --prompt="(\u@\p)[\d]> " "$@"
尝试登录
[mysql@mysql-node ~]# myin 3306
mysql: [Warning] Using a password on the command line interface can be insecure.
ERROR 1130 (HY000): Host '127.0.0.1' is not allowed to connect to this MySQL server
这是因为各个端口实例中的root用户授权的是localhost, 而不是127.0.0.1, 则可以再次添加一个针对127.0.0.1的root用户授权
或者将myin脚本中的127.0.0.1 修改为 localhost
[root@mysql-node ~]# sed -i 's/127.0.0.1/localhost/g' /usr/local/mysql/bin/myin
[root@mysql-node ~]# cat /usr/local/mysql/bin/myin
#!/bin/bash
p=$1
shift
mysql -h"localhost" -P"$p" --default-character-set=utf8mb4 --show-warnings -uroot -p'123456' -A --prompt="(\u@\p)[\d]> " "$@"
则现在可以登录各个实例了, 登录命令为"myin port"
登录3306端口实例
[root@mysql-node ~]# myin 3306
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 27
Server version: 8.0.12 MySQL Community Server - GPL
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.
(root@mysql.sock)[(none)]>
登录3307端口实例
[root@mysql-node ~]# myin 3307
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 28
Server version: 8.0.12 MySQL Community Server - GPL
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.
(root@mysql.sock)[(none)]>
登录3308端口实例
[root@mysql-node ~]# myin 3308
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 29
Server version: 8.0.12 MySQL Community Server - GPL
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.
(root@mysql.sock)[(none)]>

生产环境下的思路: 同一个业务库单独放在一个实例下, 不要混用数据库. 单机多实例间可以做主从或主主同步, 也可以在多机多实例之间坐主从或主主同步.
比如:
A机器有三个实例:  3310, 3311, 3312
B机器有三个实例:  3310, 3311, 3312
C机器有三个实例:  3310, 3311, 3312

则三台机器的每个对应的端口实例之间做主从或主主同步(GTID, MGR), 一主两从, 或三主模式.  (多实例环境最好不要用3306端口, 否则经常会出现一些误操作)

四.  Mysql8.0使用过程中踩过的一些坑

1)  创建用户和授权
在mysql8.0创建用户和授权和之前不太一样了，其实严格上来讲，也不能说是不一样, 只能说是更严格, mysql8.0需要先创建用户(创建用户时要带@并指定地址, 则grant授权时的地址就是这个@后面指定的!, 否则grant授权就会报错!)和设置密码,然后才能授权。

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mysql> create user 'kevin'@'%' identified by '123456';
Query OK, 0 rows affected (0.04 sec)
mysql> grant all privileges on *.* to 'kevin'@'%' with grant option;   
Query OK, 0 rows affected (0.04 sec)
mysql> create user 'bobo'@'%' identified by '123456';    
Query OK, 0 rows affected (0.06 sec)
mysql> grant all privileges on *.* to 'bobo'@'%' with grant option;
Query OK, 0 rows affected (0.03 sec)
mysql> flush privileges;
Query OK, 0 rows affected (0.04 sec)
mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| %         | bobo             | $A$005$1VY")q?G6<^X@-6LsXrPt5C0TwlTuvHbaOa3sYF0DKViIGoRPuCF8AzwiFcim1  |
| %         | kevin            | $A$005$hy`U}ZB#R::rA8W0y2rmwgySqzv0rmR1eTeNDSaXfQPWIsrh7ytbVdi85       |
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root             | $A$005$/VO_y^7,]6;2qxggBLmJzhA0Qylu5/AHuRScZ/ykKedgZKh/6krOIzPs2       |
+-----------+------------------+------------------------------------------------------------------------+

如果还是用Mysql5.7及之前版本的直接授权的方法, 会有报错:

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mysql> grant all privileges on *.* to 'shibo'@'%' identified by '123456';
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'identified by '123456'' at line 1

2)  Mysql8.0默认是不能使用root账号进行远程登录的! root账号只能本地登录!

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mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| %         | bobo             | $A$005$1VY")q?G6<^X@-6LsXrPt5C0TwlTuvHbaOa3sYF0DKViIGoRPuCF8AzwiFcim1 |
| %         | kevin            | $A$005$hy`U}ZB#R::rA8W0y2rmwgySqzv0rmR1eTeNDSaXfQPWIsrh7ytbVdi85 |
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | root             | $A$005$/VO_y^7,]6;2qxggBLmJzhA0Qylu5/AHuRScZ/ykKedgZKh/6krOIzPs2 |
+-----------+------------------+------------------------------------------------------------------------+
6 rows in set (0.00 sec)
如果想要远程登录, 则需要进行update更新下root账号的权限
mysql> update mysql.user set host='%' where user="root";
Query OK, 1 row affected (0.10 sec)
Rows matched: 1  Changed: 1  Warnings: 0
mysql> flush privileges;
Query OK, 0 rows affected (0.14 sec)
mysql> select host,user,authentication_string from mysql.user;
+-----------+------------------+------------------------------------------------------------------------+
| host      | user             | authentication_string                                                  |
+-----------+------------------+------------------------------------------------------------------------+
| %         | bobo             | $A$005$1VY")q?G6<^X@-6LsXrPt5C0TwlTuvHbaOa3sYF0DKViIGoRPuCF8AzwiFcim1  |
| %         | kevin            | $A$005$hy`U}ZB#R::rA8W0y2rmwgySqzv0rmR1eTeNDSaXfQPWIsrh7ytbVdi85       |
| %         | root             | $A$005$/VO_y^7,]6;2qxggBLmJzhA0Qylu5/AHuRScZ/ykKedgZKh/6krOIzPs2       |
| localhost | mysql.infoschema | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.session    | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
| localhost | mysql.sys        | $A$005$THISISACOMBINATIONOFINVALIDSALTANDPASSWORDTHATMUSTNEVERBRBEUSED |
+-----------+------------------+------------------------------------------------------------------------+
6 rows in set (0.00 sec)

这样就能在远程使用root账号登录该mysql8.0的数据库了

3) 修改root账号权限, 允许root账号远程登录后, 用navicat进行mysql的远程连接时，出现了弹窗报错：

出现这个原因是mysql8 之前的版本中加密规则是mysql_native_password, 而在mysql8之后,加密规则是caching_sha2_password, 解决问题方法有两种:
1) 一种是升级navicat驱动;
2) 一种是把mysql用户登录密码加密规则还原成mysql_native_password;

这里选择第二种方法来解决:

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#修改加密规则
mysql> ALTER USER 'root'@'%' IDENTIFIED BY '123456' PASSWORD EXPIRE NEVER;       
Query OK, 0 rows affected (0.16 sec)
#更新一下用户的密码
mysql> ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY '123456';
Query OK, 0 rows affected (0.08 sec)
#刷新权限
mysql> FLUSH PRIVILEGES;
Query OK, 0 rows affected (0.03 sec)

这样问题就解决了。

4) sqlyog链接时出现2058异常

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1) 使用sqlyog链接时会出现2058的异常，此时我们需要修改mysql，命令行登录mysql（与修改密码中登录相同，使用修改后的密码），然后执行下面的命令：
   mysql > ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password';
   其中password为自己修改的密码。然后SQLyog中重新连接，则可连接成功，OK。
2) 如果报错：ERROR 1396 (HY000): Operation ALTER USER failed for 'root'@'localhost'则使用下面命令：
   mysql > ALTER USER 'root'@'%' IDENTIFIED WITH mysql_native_password BY 'password';

5) 修改默认编码方式

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mysql8.0默认编码方式为utf8mb4，因此使用时不需要修改，可使用如下命令查看：
mysql > SHOW VARIABLES WHERE Variable_name LIKE 'character_set_%' OR Variable_name LIKE 'collation%';
如果需要修改其他编码方式，比如需要修改为utf8mb4，可以使用如下方式：
修改mysql配置文件my.cnf, 找到后请在以下三部分里添加如下内容：
[client]
default-character-set = utf8mb4
[mysql]
default-character-set = utf8mb4
[mysqld]
character-set-client-handshake = FALSE
character-set-server = utf8mb4
collation-server = utf8mb4_unicode_ci
init_connect='SET NAMES utf8mb4'
然后重启mysqld服务即可, 其中:
character_set_client  (客户端来源数据使用的字符集)
character_set_connection     (连接层字符集)
character_set_database   (当前选中数据库的默认字符集)
character_set_results (查询结果字符集)
character_set_server (默认的内部操作字符集)
========================================
数据库连接参数中:
characterEncoding=utf8 会被自动识别为utf8mb4，也可以不加这个参数，会自动检测。
而autoReconnect=true 是必须加上的。

6) 部分参数配置查询命令

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#查询mysql最大连接数设置
mysql> show global variables like 'max_conn%';
mysql> SELECT @@MAX_CONNECTIONS AS 'Max Connections';
# 查看最大链接数
mysql> show global status like 'Max_used_connections';
# 查看慢查询日志是否开启以及日志位置
mysql> show variables like 'slow_query%';
# 查看慢查询日志超时记录时间
mysql> show variables like 'long_query_time';
# 查看链接创建以及现在正在链接数
mysql> show status like 'Threads%';
# 查看数据库当前链接
mysql> show processlist;
# 查看数据库配置
mysql> show variables like '%quer%'; 

via https://www.cnblogs.com/kevingrace/p/10482469.html

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