Docker - 部署 MySQL 5.7 数据库容器

环境信息

操作系统：

$ cat /etc/centos-release
CentOS Linux release 7.7.1908 (Core)
$ uname --kernel-release
3.10.0-1062.el7.x86_64

Docker 版本：

$ docker version
Client: Docker Engine - CommunityVersion:           19.03.11API version:       1.40Go version:        go1.13.10Git commit:        42e35e61f3Built:             Mon Jun  1 09:13:48 2020OS/Arch:           linux/amd64Experimental:      falseServer: Docker Engine - CommunityEngine:Version:          19.03.11API version:      1.40 (minimum version 1.12)Go version:       go1.13.10Git commit:       42e35e61f3Built:            Mon Jun  1 09:12:26 2020OS/Arch:          linux/amd64Experimental:     falsecontainerd:Version:          1.2.13GitCommit:        7ad184331fa3e55e52b890ea95e65ba581ae3429runc:Version:          1.0.0-rc10GitCommit:        dc9208a3303feef5b3839f4323d9beb36df0a9dddocker-init:Version:          0.18.0GitCommit:        fec3683

部署 MySQL 5.7 数据库容器

1、访问 Docker Hub，搜索 mysql，过滤出 5.7 的版本。

2、拉取 MySQL 5.7.30 镜像。

$ docker pull mysql:5.7.30
5.7.30: Pulling from library/mysql
afb6ec6fdc1c: Pull complete
0bdc5971ba40: Pull complete
97ae94a2c729: Pull complete
f777521d340e: Pull complete
1393ff7fc871: Pull complete
a499b89994d9: Pull complete
7ebe8eefbafe: Pull complete
4eec965ae405: Pull complete
a531a782d709: Pull complete
270aeddb45e3: Pull complete
b25569b61008: Pull complete
Digest: sha256:d16d9ef7a4ecb29efcd1ba46d5a82bda3c28bd18c0f1e3b86ba54816211e1ac4
Status: Downloaded newer image for mysql:5.7.30
docker.io/library/mysql:5.7.30

3、查看拉取的镜像。

$ docker images
REPOSITORY          TAG                 IMAGE ID            CREATED             SIZE
mysql               5.7.30              a4fdfd462add        12 days ago         448MB

4、运行镜像，并设置 MySQL root 用户的密码。

$ docker run --interactive --detach --name mysql --publish 3306:3306 --env MYSQL_ROOT_PASSWORD=123456 mysql:5.7.30

--publish 3306:3306 宿主机的 3306 端口映射到容器的 3306 端口。

--env MYSQL_ROOT_PASSWORD=123456 设置 MySQL root 用户的密码。

5、列出正在运行的容器。

$ docker ps
CONTAINER ID        IMAGE               COMMAND                  CREATED             STATUS              PORTS                               NAMES
21fb901d85e6        mysql:5.7.30        "docker-entrypoint.s…"   10 seconds ago      Up 9 seconds        0.0.0.0:3306->3306/tcp, 33060/tcp   mysql

修改 MySQL 的字符集

1、进入容器。

$ docker exec --interactive --tty mysql /bin/bash

2、在容器中使用 MySQL 客户端连接服务端。

root@21fb901d85e6:/# mysql --user root --password
Enter password: 123456
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.30 MySQL Community Server (GPL)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.

3、连接到 MySQL 服务端之后，通过 status 命令获取服务端的状态信息。

mysql> status
--------------
mysql  Ver 14.14 Distrib 5.7.30, for Linux (x86_64) using  EditLine wrapperConnection id:       3
Current database:
Current user:       root@localhost
SSL:            Not in use
Current pager:      stdout
Using outfile:      ''
Using delimiter:    ;
Server version:     5.7.30 MySQL Community Server (GPL)
Protocol version:   10
Connection:     Localhost via UNIX socket
Server characterset:    latin1
Db     characterset:    latin1
Client characterset:    latin1
Conn.  characterset:    latin1
UNIX socket:        /var/run/mysqld/mysqld.sock
Uptime:         11 min 23 secThreads: 2  Questions: 9  Slow queries: 0  Opens: 105  Flush tables: 1  Open tables: 98  Queries per second avg: 0.013
--------------

从第 15 ~ 18 行可以看出，当前服务端、数据库和客户端等的字符集都是 latin1，接下来我们需要修改这些字符集。

4、因为 MySQL 容器中没有 vi 编辑器，所以我们需要先回到宿主机。接着将 MySQL 容器中 MySQL 配置文件复制到宿主机的根目录下。

docker cp mysql:/etc/mysql/mysql.cnf /

注意：复制之前请确保没有同名的文件。

5、修改 mysql.cnf 文件，添加以下内容。

[mysqld]
character-set-server=utf8mb4
collation-server=utf8mb4_general_ci[client]
default-character-set=utf8mb4

6、修改完成之后，将该文件复制到 MySQL 容器的 /etc/mysql/ 目录下。

$ docker cp /mysql.cnf mysql:/etc/mysql/

7、重启 MySQL 容器。

$ docker restart mysql

8、进入容器。

$ docker exec --interactive --tty mysql /bin/bash

9、重新连接 MySQL 服务端。

root@21fb901d85e6:/# mysql --user root --password
Enter password: 123456
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 2
Server version: 5.7.30 MySQL Community Server (GPL)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.

10、执行 status 命令，可以看到服务端、数据库和客户端等的字符集都是 utf8mb4。

mysql> status
--------------
mysql  Ver 14.14 Distrib 5.7.30, for Linux (x86_64) using  EditLine wrapperConnection id:       2
Current database:
Current user:       root@localhost
SSL:            Not in use
Current pager:      stdout
Using outfile:      ''
Using delimiter:    ;
Server version:     5.7.30 MySQL Community Server (GPL)
Protocol version:   10
Connection:     Localhost via UNIX socket
Server characterset:    utf8mb4
Db     characterset:    utf8mb4
Client characterset:    utf8mb4
Conn.  characterset:    utf8mb4
UNIX socket:        /var/run/mysqld/mysqld.sock
Uptime:         1 min 44 secThreads: 1  Questions: 5  Slow queries: 0  Opens: 105  Flush tables: 1  Open tables: 98  Queries per second avg: 0.048
--------------

参考信息

MySQL - Server System Variables

MySQL - Character Sets and Collations in MySQL