最近在整理数据库的工作学习笔记，测试机CentOS环境安装MySQL 8.0.20及简单使用。
附带说几句有关升级到MySQL 8的几个问题：
- 支持从MySQL 5.7（5.7.9或更高版本）升级到8.0，不支持在GA版本之间升级，不支持从非GA版本的MySQL 5.7升级到8.0；
- 建议在升级到下一个版本之前先升级到最新版本，例如，在升级到MySQL 8.0之前，请先升级到最新的MySQL 5.7版本，不支持跳过。例如，版本升级不支持从MySQL 5.6直接升级到8.0。
- 当发行版本达到GA状态时，它支持在版本系列中进行升级（从GA版本替换为GA版本），例如，从MySQL 8.0.x升级到8.0 .y。（不支持涉及开发状态的非GA版本升级）也跳过此版本，例如，支持从MySQL 8.0.x升级到8.0 .z，MySQL 8.0 .11是MySQL 8.0版本系列中的第一个GA状态版本。
不支持从MySQL 8.0降级到MySQL 5.7，或从MySQL 8.0降级到MySQL 8.0的早期版本，唯一受支持的替代方法是还原升级前做法的备份，因此，必须在开始升级过程之前备份数据。
1. MySQL源代码包下载
[root@chengyu ~ ]# mkdir -p /home/softwares/mysql/
[root@chengcheng ~]# cd /home/softwares/mysql/
[root@chengcheng mysql]# wget https://dev.mysql.com/get/downloads/MySQL-8.0/mysql-8.0.20.tar.gz
[root@chengyu mysql]# tar zxvf mysql-8.0.20.tar.gz
2.依赖包安装
相关的依赖包要求可以参考：https://dev.mysql.com/doc/refman/8.0/en/source-installation-prerequisites.html
- cmake-3.5.1以上版本
- GCC 5.3以上版本
[root@chengyu mysql]＃ yum -y install cmake3 gcc gcc-c ++ ncurses ncurses-devel libaio-devel openssl openssl-devel
3. Boost下载安装
Mysql 5.7版本更新后有很多变化，比如json等，安装必须要BOOST库，不过mysql的官网源码有带boost库的源码和不带boost库的源码两种，因此有两种安装方式，其实都是一样的，仅仅是不带boost库源码的需要单独安装boost，boost库可以大大地提高软件的开发效率，就像C#里类库，或者JAVA里类库，它是C++的类库，下载链接https://www.boost.org/，MySQL 5.7系列需要boost_1_59_0，MySQL 8需要更高的版本，这里用boost_1_70_0。
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ https://dl.bintray.com/boostorg/release/1.70.0/source/boost_1_70_0.tar.gz
[root@chengyu mysql]# tar -zxvf /home/softwares/mysql/boost_1_70_0.tar.gz -C /usr/local
[root@chengyu mysql]# cd /usr/local
[root@chengyu local]# mv boost_1_70_0 boost
[root@chengyu local]# cd boost/
[root@chengyu boost]# ./bootstrap.sh
[root@chengyu boost]# ./b2 install
4.创建MySQL安装目录和数据目录
默认情况下，从源代码编译安装MySQL时，安装一般是在/usr/local/mysql下，因为本机已经在该目录下装有MySQL 5.7.23，另建MySQL8安装目录。
[root@chengyu boost]# mkdir -p /usr/local/mysql8
[root@chengyu boost]# mkdir -p /home/mysql8
[root@chengyu boost]# mkdir -p /home/mysql8/data
[root@chengyu boost]# mkdir -p /home/mysql8/logs
5. MySQL用户创建
因为仅出于所有权目的而不是登录目的才需要该用户，所以useradd命令使用-r和-s /bin/false选项来创建对服务器主机没有登录权限的用户。
[root@chengyu boost]# groupadd mysql
[root@chengyu boost]# useradd -r -g mysql -s /bin/false mysql
[root@chengyu boost]# chown -R mysql:mysql /usr/local/mysql8
[root@chengyu boost]# chown -R mysql:mysql /home/mysql8
6.添加MySQL PATH路径并开放3307端口
[root@chengyu boost]# vim /etc/profile
#for mysql
export MYSQL_HOME=/usr/local/mysql8
export PATH=/usr/local/mysql8/bin:/usr/local/mysql8/lib:$PATH
[root@chengyu boost]# source /etc/profile
防火墙的3307端口默认没有开启，若要远程访问，需要开启这个端口，若关闭了防火墙这个就不用了。
[root@chengyu ~]# vim /etc/sysconfig/iptables
-A INPUT-m state–state NEW-m tcp-p tcp–dport 3307
-j ACCEPT
[root@chengyu ~]#/etc/init.d/iptables restart
或者systemctl restart iptables。
7.使用cmake编译并安装MySQL
[root@chengyu mysql]＃cd home/softwares/mysql/mysql-8.0.20/
[root@chengyu mysql-8.0.20]＃cmake
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql8
-DMYSQL_DATADIR=/home/mysql8/data
-DMYSQL_UNIX_ADDR=/usr/local/mysql8/mysql.sock
-DMYSQL_TCP_PORT=3307
-DDEFAULT_CHARSET=utf8mb4
-DDEFAULT_COLLATION=utf8mb4_general_ci
-DWITH_MYISAM_STORAGE_ENGINE=1
-DWITH_INNOBASE_STORAGE_ENGINE=1
-DWITH_ARCHIVE_STORAGE_ENGINE=1
-DWITH_BLACKHOLE_STORAGE_ENGINE=1
-DENABLED_LOCAL_INFILE=1
-DENABLE_DOWNLOADS=1
-DWITH_INNODB_MEMCACHED=ON
-DWITH_BOOST=/usr/local/boost
结果提示：
- running cmake version 2.8.12.2 CMake warning on CMakeLists.txt: 54 (MESSAGE): Please use cmake3 instead of cmake on this platform-please install cmake3 (please install cmake3 ) CMakeLists.txt: 84 (CMAKE_MINIMUM_REQUIRED) CMake error:
requires CMake 3.5.1 or higher.
You are running version 2.8.12.2-the configuration is incomplete and an error has occurred! &Emsp; Install cmake3:`
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ https://cmake.org/files/v3.5/cmake-3.5.1.tar.gz
[root@chengyu mysql]# tar -zxvf cmake-3.5.1.tar.gz
[root@chengyu mysql]# cd cmake-3.5.1/
[root@chengyu cmake-3.5.1]# ./bootstrap
[root@chengyu cmake-3.5.1] # gmake
[root@chengyu cmake-3.5.1] # make install
[root@chengyu cmake-3.5.1]# cmake --version
cmake version 3.5.1
CMake suite maintained and supported by Kitware (kitware.com/cmake).
重新编译安装：
[root@chengyu cmake-3.5.1] # cd /home/softwares/mysql/mysql-8.0.20/
[root@chengyu mysql-8.0.20]＃ cmake
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql8
-DMYSQL_DATADIR=/home/mysql8/data
-DMYSQL_UNIX_ADDR=/usr/local/mysql8/mysql.sock
-DMYSQL_TCP_PORT=3307
-DDEFAULT_CHARSET=utf8mb4
-DDEFAULT_COLLATION=utf8mb4_general_ci
-DWITH_MYISAM_STORAGE_ENGINE=1
-DWITH_INNOBASE_STORAGE_ENGINE=1
-DWITH_ARCHIVE_STORAGE_ENGINE=1
-DWITH_BLACKHOLE_STORAGE_ENGINE=1
-DENABLED_LOCAL_INFILE=1
-DENABLE_DOWNLOADS=1
-DWITH_INNODB_MEMCACHED=ON
-DFORCE_INSOURCE_BUILD=1
-DWITH_BOOST=/usr/local/boost
编译结果报错：
CMakeLists.txt: CMake warning on 365 (message):
This is an internally generated
-CMAKE_GENERATOR: Unix Makefiles cmake/os/
CMake error on Linux. 76 (message): Requires GCC 5.3 or higher (-dumpversion prompt 4.8.5) Call location (most recent call priority): CMakeLists.txt: 470 (inclusive)-Incomplete configuration, an error has occurred!
Please also pay attention to "/home/softwares/mysql/mysql-8.0.20/CMakeFiles/ Upgrade GCC:
解决：升级GCC，需要安装mpc、gmp、mpfr依赖包。
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ ftp://ftp.gnu.org/gnu/mpc/mpc-1.1.0.tar.gz
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ ftp://ftp.ftp.gnu.org/gnu/gmp/gmp-6.1.2.tar.bz2
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ http://ftp.gnu.org/gnu/mpfr/mpfr-4.0.2.tar.gz
[root@chengyu mysql- 8.0.20]# wget -P /home/softwares/mysql/ http://ftp.gnu.org/gnu/m4/m4-1.4.18.tar.gz
[root@chengyu mysql-8.0.20]# wget -P /home/softwares/mysql/ http://ftp.gnu.org/gnu/gcc/gcc-9.2.0/gcc-9.2.0.tar.gz
[root@chengyu mysql-8.0.20]# tar -zxvf /home/softwares/mysql/ mpc-1.1.0.tar.gz -C /home/softwares/mysql/
[root@chengyu mysql-8.0.20]# tar -zxvf /home/softwares/mysql/mpfr-4.0 .2.tar.gz -C /home/software/mysql
[root@chengyu mysql-8.0.20]# tar -jxvf /home/softwares/mysql/gmp-6.1.2.tar.bz2 -C /home/softwares/mysql/
[root@chengyu mysql-8.0.20]# tar -zxvf /home/softwares/mysql/m4-1.4.18.tar.gz -C /home/softwares/mysql/
[root@chengyu mysql-8.0.20]# tar -zxvf /home/softwares/mysql/gcc-9.2.0.tar.gz -C /home/softwares/mysql/
按顺序安装：
[root@chengyu mysql-8.0.20]# mkdir -p /usr/local/m4-1.4.18
[root@chengyu mysql-8.0.20]# mkdir -p /usr/local/gmp-6.1.2
[root@chengyu mysql-8.0.20]# mkdir -p /usr/local/mpfr-4.0.2
[root@chengyu mysql-8.0.20]# mkdir -p /usr/local/mpc-1.1.0
[root@chengyu mysql-8.0.20]# mkdir -p / usr /local/gcc-9.2.0
[root@chengyu mysql-8.0.20]# / home /softwares/mysql/m4-1.4.18/ configure --prefix = /usr/local/m4-1.4.18
[root@chengyu mysql-8.0.20]# make && make install
[root@chengyu mysql-8.0.20]# ln -s /usr/local/m4-1.4.18/bin/m4/ usr/bin/m4
[root@chengyu mysql-8.0.20]# cd /home/softwares/mysql/gmp-6.1.2/ [root@chengyu gmp-6.1.2]# ./configure --prefix = /usr/local/gmp-6.1.2
[root@chengyu gmp-6.1.2]# make && make install
[root@chengyu mysql]# cd /home/softwares/mysql/mpfr-4.0.2
[root@chengyu mpfr-4.0.2]# ./configure - -prefix=/usr/local/mpfr-4.0.2/ --with-gmp = / usr /local/gmp-6.1.2/
[root@chengyu mpfr-4.0.2]# make && make install
[root@chengyu mpfr-4.0.2]# cd /home/softwares/mysql/mpc-1.1.0/
[root@chengyu mpc-1.1.0]# ./configure --prefix = /usr/local/mpc-1.1.0 --with-gmp = /usr/local/gmp-6.1.2/ --with-mpfr=/usr/local/mpfr-4.0.2/
[root@chengyu mpc-1.1.0]# make&&make install
[root@chengyu mpc-1.1.0]# more /etc/ld.so.conf includeld。因此.conf.d /*.conf /usr/local/gmp-6.1.2/lib /usr/local/mpfr- 4.0.2/lib /usr/local/mpc-1.1.0/lib
[root@chengyu mpc-1.1.0]# ldconfig
[root@chengyu mpc-1.1.0]# cd / home /softwares/mysql/gcc-9.2.0/
[root@chengyu gcc-9.2.0]# . /configure --prefix = /usr/local/gcc-9.2.0 --with-gmp = /usr/local/gmp-6.1.2 --with-mpfr = /usr/local/mpfr-4.0.2 - with-mpc = /usr/local/mpc-1.1.0 --disable-multilib
[root@chengyugcc-9.2.0]# make && make install
[root@chengyu gcc-9.2.0]# mv /usr/bin/gcc /usr/bin/gcc4.8.5
[root@chengyu gcc- 9.2.0]# mv /usr/bin/g++ /usr/bin/g++ 4.8.5
[root@chengyu gcc-9.2.0]# ln -s /usr/local/gcc- 9.2.0/bin/gcc /usr/bin/gcc [root@chengyu gcc-9.2.0]# ln -s /usr/local/gcc-9.2.0/bin/g++ /usr/bin/g++ [root@chengyu mysql -8.0.20]# make&&make install
8.安装
再次编译结果提示：
“Make clean” or “make distclean” does not work), you can * force * use -DFORCE_INSOURCE_BUILD=1 to call cmake to compile the source internally, the configuration is incomplete, and an error will occur! Please also consider "/home /software/mysql
加上DFORCE_INSOURCE_BUILD=1编译：
提示：c++: error: unrecognized command line option ‘-std=c++14’，解决：指定 CXX 的路径 -DCMAKE_CXX_COMPILER=/usr/bin/g++。
加上-DCMAKE_CXX_COMPILER=/usr/bin/g++再次编译：
[root@chengyu mysql-8.0.20]＃ cmake \
-DCMAKE_INSTALL_PREFIX=/usr/local/mysql8 \
-DMYSQL_DATADIR=/home/mysql8/data \
-DMYSQL_UNIX_ADDR=/usr/local/mysql8/mysql.sock \
-DMYSQL_TCP_PORT=3307 \
-DDEFAULT_CHARSET=utf8mb4 \
-DDEFAULT_COLLATION=utf8mb4_general_ci \
-DWITH_MYISAM_STORAGE_ENGINE=1 \
-DWITH_INNOBASE_STORAGE_ENGINE=1 \
-DWITH_ARCHIVE_STORAGE_ENGINE=1 \
-DWITH_BLACKHOLE_STORAGE_ENGINE=1 \
-DENABLED_LOCAL_INFILE=1 \
-DENABLE_DOWNLOADS=1 \
-DWITH_INNODB_MEMCACHED=ON \
-DFORCE_INSOURCE_BUILD=1 \
-DCMAKE_CXX_COMPILER=/usr/bin/g++ \
-DWITH_BOOST=/usr/local/boost
编译完成，进行安装：
[root@chengyu mysql-8.0.20]# make&&make install
报错：
/home/softwares/mysql/mysql-8.0.20/storage/innobase/buf/buf0buf.cc: In function ‘void buf_pool_create(buf_pool_t*, ulint, ulint, std::mutex*, dberr_t&)’:
/home/softwares/mysql/mysql-8.0.20/storage/innobase/buf/buf0buf.cc:1219:44: error: ‘SYS_gettid’ was not declared in this scope
1219 | setpriority(PRIO_PROCESS, (pid_t)syscall(SYS_gettid), -20);
| ^~~~~~~~~~
make[2]: *** [storage/innobase/CMakeFiles/innobase.dir/buf/buf0buf.cc.o] Error 1
make[1]: *** [storage/innobase/CMakeFiles/innobase.dir/all] Error 2
make: *** [all] Error 2
解决：
[root@chengyu mysql-8.0.20]# vim /home/softwares/mysql/mysql-8.0.20/storage/innobase/buf/buf0buf.cc
第一行添加：#include “sys/syscall.h”
再次安装又报错：
/home/softwares/mysql/mysql-8.0.20/storage/innobase/lock/lock0lock.cc: In function ‘void lock_mark_trx_for_rollback(hit_list_t&, trx_id_t, trx_t*)’:
/home/softwares/mysql/mysql-8.0.20/storage/innobase/lock/lock0lock.cc:1171:9: error: ‘os_compare_and_swap_thread_id’ was not declared in this scope; did you mean ‘os_compare_and_swap_uint64’?
1171 | cas = os_compare_and_swap_thread_id(&trx->killed_by, 0, thread_id);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| os_compare_and_swap_uint64
make[2]: *** [storage/innobase/CMakeFiles/innobase.dir/lock/lock0lock.cc.o] Error 1
make[1]: *** [storage/innobase/CMakeFiles/innobase.dir/all] Error 2
make: *** [all] Error 2
/home/softwares/mysql/mysql-8.0.20/storage/innobase/trx/trx0trx.cc: In function ‘void trx_init(trx_t*)’:
/home/softwares/mysql/mysql-8.0.20/storage/innobase/trx/trx0trx.cc:223:5: error: ‘os_compare_and_swap_thread_id’ was not declared in this scope; did you mean ‘os_compare_and_swap_lint’?
223 | os_compare_and_swap_thread_id(&trx->killed_by, thread_id, 0);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| os_compare_and_swap_lint
/home/softwares/mysql/mysql-8.0.20/storage/innobase/trx/trx0trx.cc: In function ‘void trx_kill_blocking(trx_t*)’:
/home/softwares/mysql/mysql-8.0.20/storage/innobase/trx/trx0trx.cc:3235:5: error: ‘os_compare_and_swap_thread_id’ was not declared in this scope; did you mean ‘os_compare_and_swap_lint’?
3235 | os_compare_and_swap_thread_id(&victim_trx->killed_by, thread_id, 0);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
| os_compare_and_swap_lint
make[2]: *** [storage/innobase/CMakeFiles/innobase.dir/trx/trx0trx.cc.o] Error 1
make[1]: *** [storage/innobase/CMakeFiles/innobase.dir/all] Error 2
make: *** [all] Error 2
解决：
[root@chengyu mysql-8.0.20]# vim /home/softwares/mysql/mysql-8.0.20/storage/innobase/lock/lock0lock.cc
[root@chengyu mysql-8.0.20]# vim /home/softwares/mysql/mysql-8.0.20/storage/innobase/trx/trx0trx.cc
将 “os_compare_and_swap_thread_id” 修改为
os_compare_and_swap_lint。
好了，现在成功安装：
[root@chengyu mysql-8.0.20]# make
[root@chengyu mysql-8.0.20]# make install
9.设置开机启动
[root@chengyu mysql-8.0.20]# cd /usr/local/mysql
[root@chengyu mysql8]# cp /usr/local/mysql8/support-files/mysql.server /etc/init.d/mysqld8
[root@chengyu mysql8]# chmod 755 /etc/init.d/mysqld8
[root@chengyu mysql8]# chkconfig --add mysqld8
[root@chengyu mysql8]# chkconfig --level 345 mysqld8 on
[root@chengyu mysql8]# chkconfig --list mysqld8
Note: This output shows SysV services only and does not include native
systemd services. SysV configuration data might be overridden by native
systemd configuration.
If you want to list systemd services use 'systemctl list-unit-files'.
To see services enabled on particular target use
'systemctl list-dependencies [target]'.
mysqld8 0:off 1:off 2:on 3:on 4:on 5:on 6:off
10.创建配置文件
从MySQL 5.7.18开始，my-default.cnf不再包含在分发包中或由分发包安装，这里从其他版本的MySQL中拷贝一份my-default.cnf，并做相应的修改。
[root@chengyu mysql8]# vim /etc/my8.cnf
# For advice on how to change settings please see
# http://dev.mysql.com/doc/refman/5.6/en/server-configuration-defaults.html
# *** DO NOT EDIT THIS FILE. It's a template which will be copied to the
# *** default location during install, and will be replaced if you
# *** upgrade to a newer version of MySQL.
[mysqld]
# Remove leading # and set to the amount of RAM for the most important data
# cache in MySQL. Start at 70% of total RAM for dedicated server, else 10%.
# innodb_buffer_pool_size = 128M
# Remove leading # to turn on a very important data integrity option: logging
# changes to the binary log between backups.
# log_bin
# These are commonly set, remove the # and set as required.
basedir =/usr/local/mysql8
datadir =/home/mysql8/data
port = 3307
# server_id = .....
pid-file = /usr/local/mysql8/mysqld.pid
socket = /usr/local/mysql8/mysql.sock
# Remove leading # to set options mainly useful for reporting servers.
# The server defaults are faster for transactions and fast SELECTs.
# Adjust sizes as needed, experiment to find the optimal values.
# join_buffer_size = 128M
# sort_buffer_size = 2M
# read_rnd_buffer_size = 2M
sql_mode=NO_ENGINE_SUBSTITUTION,STRICT_TRANS_TABLES
11.初始化配置
[root@chengyu ~]# /usr/local/mysql8/bin/mysqld --defaults-file=/usr/local/mysql8/my.cnf --initialize --basedir=/usr/local/mysql8 --datadir=/home/mysql8/data --user=mysql
2020-06-11T02:18:16.129814Z 0 [Warning] [MY-010915] [Server] 'NO_ZERO_DATE', 'NO_ZERO_IN_DATE' and 'ERROR_FOR_DIVISION_BY_ZERO' sql modes should be used with strict mode. They will be merged with strict mode in a future release.
2020-06-11T02:18:16.129958Z 0 [System] [MY-013169] [Server] /usr/local/mysql8/bin/mysqld (mysqld 8.0.20) initializing of server in progress as process 9060
2020-06-11T02:18:16.138553Z 0 [Warning] [MY-013419] [InnoDB] CLOCK_MONOTONIC is unsupported, so do not change the system time when MySQL is running !
2020-06-11T02:18:16.141580Z 1 [System] [MY-013576] [InnoDB] InnoDB initialization has started.
2020-06-11T02:18:21.478754Z 1 [System] [MY-013577] [InnoDB] InnoDB initialization has ended.
2020-06-11T02:18:31.710740Z 6 [Note] [MY-010454] [Server] A temporary password is generated for root@localhost: 9?Vq)B=A6LT!
12.启动MySQL：
MySQL启动脚本和支持的服务器选项组:
[root@chengyu mysql8]# systemctl start mysqld8
[root@chengyu mysql8]# systemctl status mysqld8
● mysqld8.service - LSB: start and stop MySQL
Loaded: loaded (/etc/rc.d/init.d/mysqld8; bad; vendor preset: disabled)
Active: active (running) since Thu 2020-06-11 10:19:12 CST; 4s ago
Docs: man:systemd-sysv-generator(8)
Process: 9154 ExecStart=/etc/rc.d/init.d/mysqld8 start (code=exited, status=0/SUCCESS)
Tasks: 40
CGroup: /system.slice/mysqld8.service
├─9167 /bin/sh /usr/local/mysql8/bin/mysqld_safe --datadir=/home/mysql8/data --pid-file=/...
└─9333 /usr/local/mysql8/bin/mysqld --basedir=/usr/local/mysql8 --datadir=/home/mysql8/da...
Jun 11 10:19:09 chengyu systemd[1]: Starting LSB: start and stop MySQL...
Jun 11 10:19:09 chengyu mysqld8[9154]: Starting MySQL.Logging to '/home/mysql8/data/chengyu.err'.
Jun 11 10:19:12 chengyu mysqld8[9154]: .. SUCCESS!
Jun 11 10:19:12 chengyu systemd[1]: Started LSB: start and stop MySQL.
也可以：
[root@chengyu ~]# /usr/local/mysql8/bin/mysqld_safe --defaults-file=/usr/local/mysql8/my.cnf &
[2] 10356
[1] Done /usr/local/mysql/bin/mysqld_safe --defaults-file=/usr/local/mysql/my.cnf
[root@chengyu ~]# 2020-06-11T02:32:21.580777Z mysqld_safe Logging to '/home/mysql8/data/chengyu.err'.
2020-06-11T02:32:21.609504Z mysqld_safe Starting mysqld daemon with databases from /home/mysql8/data
13.登录数据库并修改初始密码：
使用mysqld --initialize手动执行的数据目录初始化 ， mysqld会生成一个初始随机密码，将其标记为过期，并将其写入服务器错误日志，root使用该密码连接到服务器，然后设置新密码保护初始MySQL帐户。
[root@chengyu ~]# mysql -uroot -p -P3307
Enter password:
Welcome to the MySQL monitor. Commands end with ; or \g.
Your MySQL connection id is 8
Server version: 8.0.20
Copyright (c) 2000, 2020, 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='mysql8Pass';
Query OK, 0 rows affected (0.13 sec)
mysql> show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
+--------------------+
4 rows in set (0.01 sec)
关于日常工具的安装很多时候真的十万个为什么，但无暇去深究，先按1-2-3安装完完成工作先，接下来要整理一下日常工作中常用的一些SQL。
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