一、MySQL Shell 安装
1、下载
可以在MySQL官网进行下载，地址https://dev.mysql.com/downloads/shell/。
需要根据操作系统类型、版本及glibc版本选择对应的文件下载，例如：
[root@VM-4-14-centos ~]# uname -a
Linux VM-4-14-centos 3.10.0-1160.99.1.el7.x86_64 #1 SMP Wed Sep 13 14:19:20 UTC 2023 x86_64 x86_64 x86_64 GNU/Linux
[root@VM-4-14-centos ~]# ldd --version
ldd (GNU libc) 2.17
Copyright (C) 2012 Free Software Foundation, Inc.
This is free software; see the source for copying conditions. There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
Written by Roland McGrath and Ulrich Drepper.
因此可以选择如下版本下载。
2、部署
上传文件至目标目录后解压文件。
解压后建议配置软链接。
tar -zxvf mysql-shell-8.0.35-linux-glibc2.17-x86-64bit.tar.gz可以看到对应的工具了。
ln -s mysql-shell-8.0.35-linux-glibc2.17-x86-64bit mysql-shell建议再配置一下环境变量。
将“/usr/local/mysql-shell/bin"追加至/etc/profile中。
在其他位置直接运行mysqlsh命令，即可得到如下结果：
此时，完成了mysql shell部署。
二、进行数据库备份
1、登录数据库
使用mysqlsh登录数据库，并列出库名，例如：
[root@VM-4-14-centos ~]# mysqlsh -u root -p -S /data/mysql/mysql3306/tmp/mysql.sock
Please provide the password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock': *********
Save password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'? [Y]es/[N]o/Ne[v]er (default No):
MySQL Shell 8.0.35
Copyright (c) 2016, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
Other names may be trademarks of their respective owners.
Type '\help' or '\?' for help; '\quit' to exit.
Creating a session to 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'
Fetching schema names for auto-completion... Press ^C to stop.
Your MySQL connection id is 10
Server version: 8.0.33-25 Percona Server (GPL), Release 25, Revision 60c9e2c5
No default schema selected; type \use to set one.
MySQL localhost JS > \sql
Switching to SQL mode... Commands end with ;
Fetching global names for auto-completion... Press ^C to stop.
MySQL localhost SQL > show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testdb |
| testdb1 |
+--------------------+
6 rows in set (0.0008 sec)
MySQL localhost SQL > 其中登录语法为：
mysqlsh -u root -p -S /data/mysql/mysql3306/tmp/mysql.sock输入密码后即可登录成功，输入密码后会确认是否保存密码，建议选择No(默认值）。
登录成功后，可以选择\sql ，即SQL命令模式。
2、备份整个实例
创建备份目录。
mkdir -p /data/backup登录数据库。
mysqlsh -u root -p -S /data/mysql/mysql3306/tmp/mysql.sock登录后是在js模式下，备份数据是在JS模式下进行，因此不用切换。
备份整个实例
MySQL localhost JS > util.dumpInstance("/data/backup")
Acquiring global read lock
Global read lock acquired
Initializing - done
2 out of 6 schemas will be dumped and within them 12 tables, 0 views.
2 out of 5 users will be dumped.
Gathering information - done
All transactions have been started
Locking instance for backup
Global read lock has been released
Writing global DDL files
Writing users DDL
Running data dump using 4 threads.
NOTE: Progress information uses estimated values and may not be accurate.
Writing schema metadata - done
Writing DDL - done
Writing table metadata - done
Starting data dump
129% (870 rows / ~670 rows), 0.00 rows/s, 0.00 B/s uncompressed, 0.00 B/s compressed
Dump duration: 00:00:00s
Total duration: 00:00:00s
Schemas dumped: 2
Tables dumped: 12
Uncompressed data size: 14.06 MB
Compressed data size: 4.88 MB
Compression ratio: 2.9
Rows written: 870
Bytes written: 4.88 MB
Average uncompressed throughput: 14.06 MB/s
Average compressed throughput: 4.88 MB/s
MySQL localhost JS >如无异常，即完成了实例备份。可见，备份效率比较高（4线程处理）。
备份后，备份目录结果里可以查看结果如下：
其中的主要文件解释：
@.done.json： 该文件记录了备份结束时间，每个库下每个表的大小等信息，例如：
@.json：该文件记录了客户端版本，备份类型（实例、库或表等），元数据信息以及binlog信息（点位及GTID）。例如：
@.sql, @.post.sql：这两个文件记录注释信息. 导入数据时, 我们可以通过这两个文件自定义的SQL. 在数据导入前和数据导入后执行，本次为全量备份，因此只有版本等注释信息。
库名.json： 记录的是对应库名、表等信息。
库名.sql: 具体的建库SQL脚本。
库名@表名.json:记录了对于的表的元数据信息，包括库名，表名，字段名，主键等信息。
库名@表名.sql: 具体的建表SQL脚本。
库名@表名@@*.tsv.zst： 具体数据文件。
库名@表名@@*.tsv.zst.idx： 具体索引文件。
@.users.sql : 数据库用户信息，包含创建用户以及授权的SQL脚本。
3、备份指定库
创建备份目录：重新创建一个专用于备份指定库的目录。
mkdir -p data/backup/backup_schemas
使用shellsh登录数据库，并查看当前有哪些库。
# mysqlsh -u root -p -S /data/mysql/mysql3306/tmp/mysql.sock
Please provide the password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock': *********
Save password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'? [Y]es/[N]o/Ne[v]er (default No):
MySQL Shell 8.0.35
Copyright (c) 2016, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
Other names may be trademarks of their respective owners.
Type '\help' or '\?' for help; '\quit' to exit.
Creating a session to 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'
Fetching schema names for auto-completion... Press ^C to stop.
Your MySQL connection id is 28
Server version: 8.0.33-25 Percona Server (GPL), Release 25, Revision 60c9e2c5
No default schema selected; type \use to set one.
MySQL localhost JS > \sql
Switching to SQL mode... Commands end with ;
Fetching global names for auto-completion... Press ^C to stop.
MySQL localhost SQL > show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testdb |
| testdb1 |
+--------------------+
6 rows in set (0.0010 sec) 备份指定的库（schema）,如果多个库，则用逗号分隔。
MySQL localhost SQL > \js
Switching to JavaScript mode...
MySQL localhost JS > util.dumpSchemas(['testdb'],'/data/backup/backup_schemas')
Acquiring global read lock
Global read lock acquired
Initializing - done
1 schemas will be dumped and within them 11 tables, 0 views.
Gathering information - done
All transactions have been started
Locking instance for backup
Global read lock has been released
Writing global DDL files
Running data dump using 4 threads.
NOTE: Progress information uses estimated values and may not be accurate.
Writing schema metadata - done
Writing DDL - done
Writing table metadata - done
Starting data dump
130% (862 rows / ~662 rows), 0.00 rows/s, 0.00 B/s uncompressed, 0.00 B/s compressed
Dump duration: 00:00:00s
Total duration: 00:00:00s
Schemas dumped: 1
Tables dumped: 11
Uncompressed data size: 14.06 MB
Compressed data size: 4.88 MB
Compression ratio: 2.9
Rows written: 862
Bytes written: 4.88 MB
Average uncompressed throughput: 14.06 MB/s
Average compressed throughput: 4.88 MB/s
MySQL localhost JS >以上则备份完成。
到对于目录下查看备份结果如下：
4、备份指定表
再次先创建目录。
[root@VM-4-14-centos ~]# mkdir -p /data/backup/backup_tables
[root@VM-4-14-centos ~]# cd /data/backup/backup_tables
[root@VM-4-14-centos backup_tables]#登录数据库，并查看库及表名。
[root@VM-4-14-centos backup_tables]# mysqlsh -u root -p -S /data/mysql/mysql3306/tmp/mysql.sock
Please provide the password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock': *********
Save password for 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'? [Y]es/[N]o/Ne[v]er (default No):
MySQL Shell 8.0.35
Copyright (c) 2016, 2023, Oracle and/or its affiliates.
Oracle is a registered trademark of Oracle Corporation and/or its affiliates.
Other names may be trademarks of their respective owners.
Type '\help' or '\?' for help; '\quit' to exit.
Creating a session to 'root@/data%2Fmysql%2Fmysql3306%2Ftmp%2Fmysql.sock'
Fetching schema names for auto-completion... Press ^C to stop.
Your MySQL connection id is 35
Server version: 8.0.33-25 Percona Server (GPL), Release 25, Revision 60c9e2c5
No default schema selected; type \use to set one.
MySQL localhost JS > \sql
Switching to SQL mode... Commands end with ;
Fetching global names for auto-completion... Press ^C to stop.
MySQL localhost SQL > show databases;
+--------------------+
| Database |
+--------------------+
| information_schema |
| mysql |
| performance_schema |
| sys |
| testdb |
| testdb1 |
+--------------------+
6 rows in set (0.0009 sec)
MySQL localhost SQL > use testdb1
Default schema set to `testdb1`.
Fetching global names, object names from `testdb1` for auto-completion... Press ^C to stop.
MySQL localhost testdb1 SQL > show tables;
+-------------------+
| Tables_in_testdb1 |
+-------------------+
| test1 |
+-------------------+
1 row in set (0.0014 sec)
MySQL localhost testdb1 SQL > 进行指定表的备份，如果多个表，则表名用逗号分隔。
MySQL localhost testdb1 JS > util.dumpTables('testdb1',['test1'],'/data/backup/backup_tables')
Acquiring global read lock
Global read lock acquired
Initializing - done
1 tables and 0 views will be dumped.
Gathering information - done
All transactions have been started
Locking instance for backup
Global read lock has been released
Writing global DDL files
Running data dump using 4 threads.
NOTE: Progress information uses estimated values and may not be accurate.
Writing schema metadata - done
Writing DDL - done
Writing table metadata - done
Starting data dump
100% (8 rows / ~8 rows), 0.00 rows/s, 0.00 B/s uncompressed, 0.00 B/s compressed
Dump duration: 00:00:00s
Total duration: 00:00:00s
Schemas dumped: 1
Tables dumped: 1
Uncompressed data size: 157 bytes
Compressed data size: 90 bytes
Compression ratio: 1.7
Rows written: 8
Bytes written: 90 bytes
Average uncompressed throughput: 157.00 B/s
Average compressed throughput: 90.00 B/s
MySQL localhost testdb1 JS >查看备份结果：
至此，备份数据库实例、库、表的命令已简单演示完毕，实际生产使用过程基本会用脚本实现，大家可以自行编写。