MySQL数据备份之逻辑备份工具mysqldump

2019/04/10 10:10
阅读数 31

#前言:我们知道对数据进行备份很重要,出现非正常操作可以进行对数据进行恢复,下面我们就来使用一下mysql数据库自带的一个逻辑备份工具mysqldump

1.简单概述

#mysqldump:mysql数据自带的一个备份命令

#语法格式:

mysqldump -u用户名 -p 数据库名 > 备份的文件名

 

#mysqldump逻辑备份的工作原理

1、mysqldump命令备份数据的过程,实际是把数据从mysql库里以逻辑的sql语句形式直接输出或生成备份文件的过程
2、恢复的时候就是把sql语句在数据库里面执行一遍的过程

 

#mysqldump帮助文档

[root@ctos3 ~]# mysqldump --help > 1.txt
[root@ctos3 ~]# cat 1.txt
mysqldump  Ver 10.13 Distrib 5.7.29, for Linux (x86_64)
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.

Dumping structure and contents of MySQL databases and tables.
Usage: mysqldump [OPTIONS] database [tables]
OR     mysqldump [OPTIONS] --databases [OPTIONS] DB1 [DB2 DB3...]
OR     mysqldump [OPTIONS] --all-databases [OPTIONS]

Default options are read from the following files in the given order:
/etc/my.cnf /etc/mysql/my.cnf /application/mysql/etc/my.cnf ~/.my.cnf 
The following groups are read: mysqldump client
The following options may be given as the first argument:
--print-defaults        Print the program argument list and exit.
--no-defaults           Don't read default options from any option file,
                        except for login file.
--defaults-file=#       Only read default options from the given file #.
--defaults-extra-file=# Read this file after the global files are read.
--defaults-group-suffix=#
                        Also read groups with concat(group, suffix)
--login-path=#          Read this path from the login file.
  -A, --all-databases Dump all the databases. This will be same as --databases
                      with all databases selected.
  -Y, --all-tablespaces 
                      Dump all the tablespaces.
  -y, --no-tablespaces 
                      Do not dump any tablespace information.
  --add-drop-database Add a DROP DATABASE before each create.
  --add-drop-table    Add a DROP TABLE before each create.
                      (Defaults to on; use --skip-add-drop-table to disable.)
  --add-drop-trigger  Add a DROP TRIGGER before each create.
  --add-locks         Add locks around INSERT statements.
                      (Defaults to on; use --skip-add-locks to disable.)
  --allow-keywords    Allow creation of column names that are keywords.
  --apply-slave-statements 
                      Adds 'STOP SLAVE' prior to 'CHANGE MASTER' and 'START
                      SLAVE' to bottom of dump.
  --bind-address=name IP address to bind to.
  --character-sets-dir=name 
                      Directory for character set files.
  -i, --comments      Write additional information.
                      (Defaults to on; use --skip-comments to disable.)
  --compatible=name   Change the dump to be compatible with a given mode. By
                      default tables are dumped in a format optimized for
                      MySQL. Legal modes are: ansi, mysql323, mysql40,
                      postgresql, oracle, mssql, db2, maxdb, no_key_options,
                      no_table_options, no_field_options. One can use several
                      modes separated by commas. Note: Requires MySQL server
                      version 4.1.0 or higher. This option is ignored with
                      earlier server versions.
  --compact           Give less verbose output (useful for debugging). Disables
                      structure comments and header/footer constructs.  Enables
                      options --skip-add-drop-table --skip-add-locks
                      --skip-comments --skip-disable-keys --skip-set-charset.
  -c, --complete-insert 
                      Use complete insert statements.
  -C, --compress      Use compression in server/client protocol.
  -a, --create-options 
                      Include all MySQL specific create options.
                      (Defaults to on; use --skip-create-options to disable.)
  -B, --databases     Dump several databases. Note the difference in usage; in
                      this case no tables are given. All name arguments are
                      regarded as database names. 'USE db_name;' will be
                      included in the output.
  -#, --debug[=#]     This is a non-debug version. Catch this and exit.
  --debug-check       This is a non-debug version. Catch this and exit.
  --debug-info        This is a non-debug version. Catch this and exit.
  --default-character-set=name 
                      Set the default character set.
  --delete-master-logs 
                      Delete logs on master after backup. This automatically
                      enables --master-data.
  -K, --disable-keys  '/*!40000 ALTER TABLE tb_name DISABLE KEYS */; and
                      '/*!40000 ALTER TABLE tb_name ENABLE KEYS */; will be put
                      in the output.
                      (Defaults to on; use --skip-disable-keys to disable.)
  --dump-slave[=#]    This causes the binary log position and filename of the
                      master to be appended to the dumped data output. Setting
                      the value to 1, will printit as a CHANGE MASTER command
                      in the dumped data output; if equal to 2, that command
                      will be prefixed with a comment symbol. This option will
                      turn --lock-all-tables on, unless --single-transaction is
                      specified too (in which case a global read lock is only
                      taken a short time at the beginning of the dump - don't
                      forget to read about --single-transaction below). In all
                      cases any action on logs will happen at the exact moment
                      of the dump.Option automatically turns --lock-tables off.
  -E, --events        Dump events.
  -e, --extended-insert 
                      Use multiple-row INSERT syntax that include several
                      VALUES lists.
                      (Defaults to on; use --skip-extended-insert to disable.)
  --fields-terminated-by=name 
                      Fields in the output file are terminated by the given
                      string.
  --fields-enclosed-by=name 
                      Fields in the output file are enclosed by the given
                      character.
  --fields-optionally-enclosed-by=name 
                      Fields in the output file are optionally enclosed by the
                      given character.
  --fields-escaped-by=name 
                      Fields in the output file are escaped by the given
                      character.
  -F, --flush-logs    Flush logs file in server before starting dump. Note that
                      if you dump many databases at once (using the option
                      --databases= or --all-databases), the logs will be
                      flushed for each database dumped. The exception is when
                      using --lock-all-tables or --master-data: in this case
                      the logs will be flushed only once, corresponding to the
                      moment all tables are locked. So if you want your dump
                      and the log flush to happen at the same exact moment you
                      should use --lock-all-tables or --master-data with
                      --flush-logs.
  --flush-privileges  Emit a FLUSH PRIVILEGES statement after dumping the mysql
                      database.  This option should be used any time the dump
                      contains the mysql database and any other database that
                      depends on the data in the mysql database for proper
                      restore. 
  -f, --force         Continue even if we get an SQL error.
  -?, --help          Display this help message and exit.
  --hex-blob          Dump binary strings (BINARY, VARBINARY, BLOB) in
                      hexadecimal format.
  -h, --host=name     Connect to host.
  --ignore-error=name A comma-separated list of error numbers to be ignored if
                      encountered during dump.
  --ignore-table=name Do not dump the specified table. To specify more than one
                      table to ignore, use the directive multiple times, once
                      for each table.  Each table must be specified with both
                      database and table names, e.g.,
                      --ignore-table=database.table.
  --include-master-host-port 
                      Adds 'MASTER_HOST=<host>, MASTER_PORT=<port>' to 'CHANGE
                      MASTER TO..' in dump produced with --dump-slave.
  --insert-ignore     Insert rows with INSERT IGNORE.
  --lines-terminated-by=name 
                      Lines in the output file are terminated by the given
                      string.
  -x, --lock-all-tables 
                      Locks all tables across all databases. This is achieved
                      by taking a global read lock for the duration of the
                      whole dump. Automatically turns --single-transaction and
                      --lock-tables off.
  -l, --lock-tables   Lock all tables for read.
                      (Defaults to on; use --skip-lock-tables to disable.)
  --log-error=name    Append warnings and errors to given file.
  --master-data[=#]   This causes the binary log position and filename to be
                      appended to the output. If equal to 1, will print it as a
                      CHANGE MASTER command; if equal to 2, that command will
                      be prefixed with a comment symbol. This option will turn
                      --lock-all-tables on, unless --single-transaction is
                      specified too (in which case a global read lock is only
                      taken a short time at the beginning of the dump; don't
                      forget to read about --single-transaction below). In all
                      cases, any action on logs will happen at the exact moment
                      of the dump. Option automatically turns --lock-tables
                      off.
  --max-allowed-packet=# 
                      The maximum packet length to send to or receive from
                      server.
  --net-buffer-length=# 
                      The buffer size for TCP/IP and socket communication.
  --no-autocommit     Wrap tables with autocommit/commit statements.
  -n, --no-create-db  Suppress the CREATE DATABASE ... IF EXISTS statement that
                      normally is output for each dumped database if
                      --all-databases or --databases is given.
  -t, --no-create-info 
                      Don't write table creation info.
  -d, --no-data       No row information.
  -N, --no-set-names  Same as --skip-set-charset.
  --opt               Same as --add-drop-table, --add-locks, --create-options,
                      --quick, --extended-insert, --lock-tables, --set-charset,
                      and --disable-keys. Enabled by default, disable with
                      --skip-opt.
  --order-by-primary  Sorts each table's rows by primary key, or first unique
                      key, if such a key exists.  Useful when dumping a MyISAM
                      table to be loaded into an InnoDB table, but will make
                      the dump itself take considerably longer.
  -p, --password[=name] 
                      Password to use when connecting to server. If password is
                      not given it's solicited on the tty.
  -P, --port=#        Port number to use for connection.
  --protocol=name     The protocol to use for connection (tcp, socket, pipe,
                      memory).
  -q, --quick         Don't buffer query, dump directly to stdout.
                      (Defaults to on; use --skip-quick to disable.)
  -Q, --quote-names   Quote table and column names with backticks (`).
                      (Defaults to on; use --skip-quote-names to disable.)
  --replace           Use REPLACE INTO instead of INSERT INTO.
  -r, --result-file=name 
                      Direct output to a given file. This option should be used
                      in systems (e.g., DOS, Windows) that use carriage-return
                      linefeed pairs (\r\n) to separate text lines. This option
                      ensures that only a single newline is used.
  -R, --routines      Dump stored routines (functions and procedures).
  --set-charset       Add 'SET NAMES default_character_set' to the output.
                      (Defaults to on; use --skip-set-charset to disable.)
  --set-gtid-purged[=name] 
                      Add 'SET @@GLOBAL.GTID_PURGED' to the output. Possible
                      values for this option are ON, OFF and AUTO. If ON is
                      used and GTIDs are not enabled on the server, an error is
                      generated. If OFF is used, this option does nothing. If
                      AUTO is used and GTIDs are enabled on the server, 'SET
                      @@GLOBAL.GTID_PURGED' is added to the output. If GTIDs
                      are disabled, AUTO does nothing. If no value is supplied
                      then the default (AUTO) value will be considered.
  --single-transaction 
                      Creates a consistent snapshot by dumping all tables in a
                      single transaction. Works ONLY for tables stored in
                      storage engines which support multiversioning (currently
                      only InnoDB does); the dump is NOT guaranteed to be
                      consistent for other storage engines. While a
                      --single-transaction dump is in process, to ensure a
                      valid dump file (correct table contents and binary log
                      position), no other connection should use the following
                      statements: ALTER TABLE, DROP TABLE, RENAME TABLE,
                      TRUNCATE TABLE, as consistent snapshot is not isolated
                      from them. Option automatically turns off --lock-tables.
  --dump-date         Put a dump date to the end of the output.
                      (Defaults to on; use --skip-dump-date to disable.)
  --skip-opt          Disable --opt. Disables --add-drop-table, --add-locks,
                      --create-options, --quick, --extended-insert,
                      --lock-tables, --set-charset, and --disable-keys.
  -S, --socket=name   The socket file to use for connection.
  --secure-auth       Refuse client connecting to server if it uses old
                      (pre-4.1.1) protocol. Deprecated. Always TRUE
  --ssl-mode=name     SSL connection mode.
  --ssl               Deprecated. Use --ssl-mode instead.
                      (Defaults to on; use --skip-ssl to disable.)
  --ssl-verify-server-cert 
                      Deprecated. Use --ssl-mode=VERIFY_IDENTITY instead.
  --ssl-ca=name       CA file in PEM format.
  --ssl-capath=name   CA directory.
  --ssl-cert=name     X509 cert in PEM format.
  --ssl-cipher=name   SSL cipher to use.
  --ssl-key=name      X509 key in PEM format.
  --ssl-crl=name      Certificate revocation list.
  --ssl-crlpath=name  Certificate revocation list path.
  --tls-version=name  TLS version to use, permitted values are: TLSv1, TLSv1.1,
                      TLSv1.2
  --server-public-key-path=name 
                      File path to the server public RSA key in PEM format.
  --get-server-public-key 
                      Get server public key
  -T, --tab=name      Create tab-separated textfile for each table to given
                      path. (Create .sql and .txt files.) NOTE: This only works
                      if mysqldump is run on the same machine as the mysqld
                      server.
  --tables            Overrides option --databases (-B).
  --triggers          Dump triggers for each dumped table.
                      (Defaults to on; use --skip-triggers to disable.)
  --tz-utc            SET TIME_ZONE='+00:00' at top of dump to allow dumping of
                      TIMESTAMP data when a server has data in different time
                      zones or data is being moved between servers with
                      different time zones.
                      (Defaults to on; use --skip-tz-utc to disable.)
  -u, --user=name     User for login if not current user.
  -v, --verbose       Print info about the various stages.
  -V, --version       Output version information and exit.
  -w, --where=name    Dump only selected records. Quotes are mandatory.
  -X, --xml           Dump a database as well formed XML.
  --plugin-dir=name   Directory for client-side plugins.
  --default-auth=name Default authentication client-side plugin to use.
  --enable-cleartext-plugin 
                      Enable/disable the clear text authentication plugin.

Variables (--variable-name=value)
and boolean options {FALSE|TRUE}  Value (after reading options)
--------------------------------- ----------------------------------------
all-databases                     FALSE
all-tablespaces                   FALSE
no-tablespaces                    FALSE
add-drop-database                 FALSE
add-drop-table                    TRUE
add-drop-trigger                  FALSE
add-locks                         TRUE
allow-keywords                    FALSE
apply-slave-statements            FALSE
bind-address                      (No default value)
character-sets-dir                (No default value)
comments                          TRUE
compatible                        (No default value)
compact                           FALSE
complete-insert                   FALSE
compress                          FALSE
create-options                    TRUE
databases                         FALSE
default-character-set             utf8
delete-master-logs                FALSE
disable-keys                      TRUE
dump-slave                        0
events                            FALSE
extended-insert                   TRUE
fields-terminated-by              (No default value)
fields-enclosed-by                (No default value)
fields-optionally-enclosed-by     (No default value)
fields-escaped-by                 (No default value)
flush-logs                        FALSE
flush-privileges                  FALSE
force                             FALSE
hex-blob                          FALSE
host                              (No default value)
ignore-error                      (No default value)
include-master-host-port          FALSE
insert-ignore                     FALSE
lines-terminated-by               (No default value)
lock-all-tables                   FALSE
lock-tables                       TRUE
log-error                         (No default value)
master-data                       0
max-allowed-packet                25165824
net-buffer-length                 1046528
no-autocommit                     FALSE
no-create-db                      FALSE
no-create-info                    FALSE
no-data                           FALSE
order-by-primary                  FALSE
port                              3306
quick                             TRUE
quote-names                       TRUE
replace                           FALSE
routines                          FALSE
set-charset                       TRUE
single-transaction                FALSE
dump-date                         TRUE
socket                            /application/mysql/tmp/mysql.sock
secure-auth                       TRUE
ssl                               TRUE
ssl-verify-server-cert            FALSE
ssl-ca                            (No default value)
ssl-capath                        (No default value)
ssl-cert                          (No default value)
ssl-cipher                        (No default value)
ssl-key                           (No default value)
ssl-crl                           (No default value)
ssl-crlpath                       (No default value)
tls-version                       (No default value)
server-public-key-path            (No default value)
get-server-public-key             FALSE
tab                               (No default value)
triggers                          TRUE
tz-utc                            TRUE
user                              (No default value)
verbose                           FALSE
where                             (No default value)
plugin-dir                        (No default value)
default-auth                      (No default value)
enable-cleartext-plugin           FALSE
View Code

 

#mysqldump备份使用场景

1、迁移或者升级数据库时
2、增加从库时候
3、因为硬件或特殊异常情况,主库或从库宕机
4、人为的DDL,DML语句,主从库没办法了,所有库都会执行
5、跨机房灾备,需要备份

 

2.mysqldump的一些关键参数

1、 -B    --databases  指定多个库。增加建库语句和use语句
2、 --compact   去掉注释,适合调试输出
3、 -A     --all-databases   备份所有库
4、 -F 刷新binlog  日志
5、--master-data   增加binlog日志文件名及对应的位置点
6、-x  --lock-all-tables     全局的读锁,会阻止对所有表的写入操作
7、 -l     该锁不会阻止读,也不会阻止新的数据插入
8、 -d  只备份表结构
9、 -t  只备份数据
10、 --signle-transaction   适合innodb事务数据库备份

 

#在介绍相关参数的时候,我们先来了解一下-e参数

#作用:加上-e参数可以直接在外面交互式查看数据库里面的东西,而不用登录到数据库里面

#例1:查看数据库

[root@cots3 ~]# mysql -uroot -p -e "show databases;"
Enter password: 
+--------------------+
| Database           |
+--------------------+
| information_schema |
| data               |
| db                 |
| mysql              |
| performance_schema |
| sys                |
+--------------------+

#例二:可以执行多个操作,如进入某个数据库然后查看表

[root@cots3 ~]# mysql -uroot -p -e "use data;show tables;"
Enter password: 
+----------------+
| Tables_in_data |
+----------------+
| Student        |
+----------------+

#例三:查看数据库连接情况,也可以show full processlist查看完整的语句

[root@cots3 ~]# mysql -uroot -p -e "show processlist;"
Enter password: 
+----+------+-----------+------+---------+------+----------+------------------+
| Id | User | Host      | db   | Command | Time | State    | Info             |
+----+------+-----------+------+---------+------+----------+------------------+
| 31 | root | localhost | NULL | Query   |    0 | starting | show processlist |
+----+------+-----------+------+---------+------+----------+------------------+

#参数介绍:id:进程,user:用户,host:连接的主机,db:使用的哪个库,command:执行了什么命令,time:多长时间,state:状态,info:信息

 

#1.-B参数

#作用:如果删除了数据库,不加-B参数,备份回来是会报错的,除非将数据库创建回来,备份时候加了-B参数会有自动建库语句

#例子:我们来演示以下加-B和不加-B的效果

#1.先演示不加-B参数的效果

#提示:我这里创建的表的时候,库和表的字符集都是使用UTF8,以免导出中文的时候出现乱码
mysql> create database data character set=utf8;  #表会随着库的字符集
Query OK, 1 row affected (0.00 sec)

使用root用户登录将data数据库备份到/opt目录下
[root@ctos3 ~]# mysqldump -uroot -p data > /opt/mysql.bak.sql
Enter password: 

#查看备份的东西
[root@ctos3 ~]# grep -Ev "#|\*|--|^$" /opt/mysql.bak.sql 
DROP TABLE IF EXISTS `Student`;
CREATE TABLE `Student` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `name` char(20) NOT NULL,
  `age` varchar(16) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
LOCK TABLES `Student` WRITE;
INSERT INTO `Student` VALUES (1,'aa','19'),(2,'bb','20'),(3,'张冲','21');
UNLOCK TABLES;
#恢复

#将表删除再恢复
[root@ctos3 ~]# mysql -uroot -p -e "use data;drop table Student;" #删除表
Enter password: 

[root@cots3 ~]# mysql -uroot -p -e "select * from data.Student;" #确认表有没有删除
Enter password: 
ERROR 1146 (42S02) at line 1: Table 'data.Student' doesn't exist

[root@ctos3 ~]# mysql -uroot -p data < /opt/mysql.bak.sql  #进行恢复,没问题
Enter password: 

[root@ctos3 ~]# mysql -uroot -p -e "select * from data.Student;" #查看
Enter password: 
+----+--------+-----+
| id | name   | age |
+----+--------+-----+
|  1 | aa     | 19  |
|  2 | bb     | 20  |
|  3 | 张冲   | 21  |
+----+--------+-----+
#问题:如果删除了数据库,如果备份的时候不加-B参数,备份回来是会报错的,除非将数据库创建回来

mysql> drop database data;
Query OK, 1 row affected (0.02 sec)

[root@ctos3 ~]# mysql -uroot -p data < /opt/mysql.bak.sql  #恢复的时候就会报错,备份的时候没有加-B参数,没有建库语句
Enter password: 
ERROR 1049 (42000): Unknown database 'data'

[root@ctos3 ~]# mysql -uroot -p -e "create database data;" #将数据库创建回来
Enter password: 
[root@ctos3 ~]# mysql -uroot -p -e "show databases;" | grep -E "data"
Enter password: 
data

[root@ctos3 ~]# mysql -uroot -p data < /opt/mysql.bak.sql  #恢复数据
Enter password: 

[root@ctos3 ~]# mysql -uroot -p -e "use data;select * from Student;" #查看
Enter password: 
+----+--------+-----+
| id | name   | age |
+----+--------+-----+
|  1 | aa     | 19  |
|  2 | bb     | 20  |
|  3 | 张冲   | 21  |
+----+--------+-----+
 

#2.演示加-B参数备份
[root@cots3 ~]# mysqldump -uroot -p -B data > /opt/mysql.bak_B.sql  #首先使用-B进行备份
Enter password: 

[root@cots3 ~]# cd /opt/
[root@cots3 opt]# ls
mysql.bak_B.sql  mysql.bak.sql
[root@cots3 opt]# diff mysql.bak.sql  mysql.bak_B.sql  #对比一下加-B和不加的区别,加了-B会有创建数据库和连接数据库的命令
18a19,26
> -- Current Database: `data`
> --
> 
> CREATE DATABASE /*!32312 IF NOT EXISTS*/ `data` /*!40100 DEFAULT CHARACTER SET latin1 */;
> 
> USE `data`;
> 
> --
52c60
< -- Dump completed on 2020-03-12  5:46:28
---
> -- Dump completed on 2020-03-12  5:53:11


[root@cots3 ~]# mysql -uroot -p -e "drop database data;" #删除数据库
Enter password: 
[root@cots3 ~]# mysql -uroot -p < /opt/mysql.bak_B.sql  #然后恢复
Enter password: 
[root@cots3 ~]# mysql -uroot -p -e "select * from data.Student;"
Enter password: 
+----+--------+-----+
| id | name   | age |
+----+--------+-----+
|  1 | aa     | 19  |
|  2 | bb     | 20  |
|  3 | 张冲   | 21  |
+----+--------+-----+
#提示:备份的时候加入-B参数好点,还原的时候不用加创建库
演练

 

#2.-d参数:只备份表结构

#例子:只备份data库的所有表的结构

[root@cots3 ~]# mysqldump -uroot -p  --compact -d data
Enter password: 
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `Student` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `name` char(20) NOT NULL,
  `age` varchar(16) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB AUTO_INCREMENT=4 DEFAULT CHARSET=utf8;
/*!40101 SET character_set_client = @saved_cs_client */;
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `test` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `name` char(20) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

#查看test表结构

[root@cots3 ~]# mysqldump -uroot -p  --compact -d data test
Enter password: 
/*!40101 SET @saved_cs_client     = @@character_set_client */;
/*!40101 SET character_set_client = utf8 */;
CREATE TABLE `test` (
  `id` int(4) NOT NULL AUTO_INCREMENT,
  `name` char(20) NOT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=latin1;
/*!40101 SET character_set_client = @saved_cs_client */;

#提示:--compact参数会提供较少的输出(对调试很有用)

 

#3.-t参数:只输出数据

[root@cots3 ~]# mysqldump -uroot -p --compact -t data
Enter password: 
INSERT INTO `Student` VALUES (1,'aa','19'),(2,'bb','20'),(3,'张冲','21');

 

#4.可以使用gzip对备份的数据进行压缩

#好处:使用压缩备份的话将会缩小文件大小,减少占用空间

[root@cots3 ~]# mysqldump -uroot -p -B data | gzip > /opt/mysql.bak_sql.gz
Enter password:

[root@cots3 ~]# ls -lh /opt/
total 8.0K
-rw-r--r-- 1 root root 2.6K Mar 12 06:32 mysql.bak_B.sql
-rw-r--r-- 1 root root  851 Mar 12 07:56 mysql.bak_sql.gz

 

3.备份库

#3.1.备份单个库

[root@cots3 ~]# mysqldump -uroot -p -B data > /opt/mysql.bak_data.sql
Enter password: 

 

#3.2.备份多个库

[root@cots3 ~]# mysqldump -uroot -p -B data db | gzip > /opt/mysql.bak.sql.gz
Enter password: 

#提示:-B参数是关键,在-B参数后指定库名,空格隔开备份多个库

#注意点:在备份多个数据库的时候最好使用root去备份,要不然如果使用别的用户取备份,在创建用户的时候如果没有指定那个库,那么就会相对应的备份不了

#演示效果

[root@cots3 ~]# mysql -uroot -p -e "grant all privileges on db.* to test@localhost identified by 'guoke123';" #创建一个test用户,指定管理db库
Enter password: 

[root@cots3 ~]# mysqldump -utest -p -B data db | gzip > /opt/test_bak1.sql.gz #备份到其他库就会报错,没有权限
Enter password: 
mysqldump: Got error: 1044: Access denied for user 'test'@'localhost' to database 'data' when selecting the database
[root@cots3 ~]# mysqldump -utest -p -B  db | gzip >  /opt/test_bak1.sql.gz #备份自己管理的就可以
Enter password: 

 

#3.3.分库备份

#简单理解:分库就是将数据库里面的库分开来进行备份

#注意点:每个库都可以用对应备份的库作为库名结尾加.sql

 #分库备份的意义:有时一个企业的数据库里会有多个库,例如(www,guoke,blog),但是有时候出问题的可能只是某一个库,如果在备份时把所有的库都备份成一个数据文件的话,恢复某一个库的数据时就比较麻烦了

#备份方法

#方法1:使用一条命令完成

[root@cots3 ~]# mkdir /opt/back
[root@cots3 ~]# mysql -uroot -p -e "show databases;" | grep -Evi "database|infor|per|sys" | sed -r 's#^([a-z].*$)#mysqldump -uroot -p  -B \1|gzip >/opt/back/\1.sql.gz#g' | bash
Enter password: 
Enter password: 
Enter password: 
Enter password: 
[root@cots3 ~]# ls -l /opt/back/
total 232
-rw-r--r-- 1 root root    851 Mar 12 08:14 data.sql.gz
-rw-r--r-- 1 root root   1212 Mar 12 08:14 db.sql.gz
-rw-r--r-- 1 root root 229070 Mar 12 08:14 mysql.sql.gz
#提示:为什么是输入四次密码呢,因为第一次是登录的密码,其余3次是备份3个库的时候使用
#命令解释:首先使用grep过滤出想要备份的库,然后使用sed来进行替换,-r是支持扩展表达式

#方法二:如果库少的话就一个库对一个应该文件,一个一个来,如果库多久写脚本,用for循环

[root@cots3 ~]# mkdir /opt/bak

[root@cots3 ~]# cat fenku.sh 
#!/bin/bash

for dbname in `mysql -uroot -p"guoke123" -e "show databases;" | grep -Evi "database|infor|per|sys"`
do
    mysqldump -uroot -p"guoke123" --events -B $dbname |gzip > /opt/bak/${dbname}.sql.gz
done

[root@cots3 ~]# ls -l /opt/bak/ #查看效果
total 232
-rw-r--r-- 1 root root    868 Mar 12 08:23 data.sql.gz
-rw-r--r-- 1 root root   1230 Mar 12 08:23 db.sql.gz
-rw-r--r-- 1 root root 229088 Mar 12 08:23 mysql.sql.gz

4.备份表

4.1.备份单个表

#语法格式:mysqldump  -u 用户名 -p 数据库名  表名  >  备份的文件名

#例子:

[root@cots3 ~]# mysqldump -uroot -p db test > /opt/mysql_test.sql
Enter password: 

[root@cots3 ~]# ls -l /opt/ | grep mysql_test
-rw-r--r-- 1 root root 1934 Mar 12 08:26 mysql_test.sql

#提示:备份一个表的时候不要加-B,要不然所有表都会出来,就会报错

 

4.2.备份多个表

#语法格式:mysqldump -u 用于名  -p   数据库名  表名1   表名2   >  备份的文件名

#例子:

[root@cots3 ~]# mysqldump -uroot -p db guoke test > /opt/mysql_table.sql

 

#4.3使用脚本进行分库分表备份

[root@ctos3 ~]# cat bak.sh 
#!/bin/bash

MYUSER="root"
MYPASS="guoke123"
MYLOG="mysql -u$MYUSER -p$MYPASS -e"
MYDUMP="mysqldump -u$MYUSER -p$MYPASS -x -F"
DBLIST=$($MYLOG  "show databases;" | sed 1d | grep -Ev 'info|mysq|per|sys')
DIR=/backup
[ ! -d $DIR ] && mkdir $DIR
cd $DIR

for dbname in $DBLIST
do
 TABLIST=$($MYLOG "show tables from $dbname;" | sed 1d)
for tabname in $TABLIST
do
  mkdir -p $DIR/$dbname
   $MYDUMP $dbname $tabname  --events |gzip > $DIR/${dbname}/${tabname}_$(date +%F_%T).sql.gz
done
done

 

#备份的效果

[root@ctos3 ~]# ls -l /backup/
total 0
drwxr-xr-x. 2 root root 45 Mar 13 09:14 data
drwxr-xr-x. 2 root root 48 Mar 13 09:14 db
[root@ctos3 ~]# ls -l /backup/data/
total 4
-rw-r--r--. 1 root root 742 Mar 13 09:14 test_2020-03-13_09:14:26.sql.gz
[root@ctos3 ~]# ls -l /backup/db/
total 4
-rw-r--r--. 1 root root 699 Mar 13 09:14 student_2020-03-13_09:14:27.sql.gz

 

5.恢复数据

#1.一般的恢复数据库命令

[root@cots3 ~]# mysql -uroot -p < /opt/mysql_test1.sql #备份时加-B参数恢复方法

[root@cots3 ~]# mysql -uroot -p test < /opt/mysql_test1.sql  #备份时不加-B参数方法

#2.恢复分库分表备份的数据

#思路:先将所有库找出来,然后使用for循环将其恢复。
#提示:如果备份的时候是压缩了,可以先解压,或者可以使用sed过滤数据库名字出来,使用for循环恢复

#例子:

#1.首先备份所有数据库
[root@cots3 ~]# mysql -uroot -p -e "show databases;" | grep -Evi "database|infor|per|sys|mysql" | sed -r 's#^([a-z].*$)#mysqldump -uroot -p  -B \1|gzip >/opt/back/\1.sql.gz#g' | bash
Enter password: 
Enter password: 
Enter password: 
[root@cots3 ~]# ls -l /opt/back/
total 8
-rw-r--r-- 1 root root  851 Mar 12 08:48 data.sql.gz
-rw-r--r-- 1 root root 1212 Mar 12 08:48 db.sql.gz

#2.将数据库删除,进行解压缩再进行恢复
mysql> drop database data;
Query OK, 2 rows affected (0.02 sec)

mysql> drop database db;
Query OK, 3 rows affected (0.02 sec)

#3.将备份的文件解压缩
[root@cots3 ~]# cd /opt/back/
[root@cots3 back]# ls
data.sql.gz  db.sql.gz
[root@cots3 back]# gunzip *
[root@cots3 back]# ls
data.sql  db.sql

#4.使用for循环恢复
[root@cots3 ~]# for dbname in `ls /opt/back/*.sql`;do mysql -uroot -p < ${dbname};done
Enter password: 
Enter password:

 

#3.使用source恢复数据库

#方法:登录数据库mysql>source 备份文件

#例子:

[root@cots3 bak]# mysql -uroot -p -e "drop database data;" #将data库删除
mysql> system ls /opt/bak
data.sql  db.sql  mysql.sql
mysql> source /opt/bak/data.sql #进行恢复

 

6.全量备份与增量备份

#全量备份

全量备份就是把数据库中所有的数据进进行备份

#例子:

[root@cots3 ~]# mysqldump -uroot -p --events -F -A -B |gzip > /opt/back/mysqlback_$(date +%F).sql.gz  #备份所有库
Enter password: 
[root@cots3 ~]# ls -l /opt/back/mysqlback_2020-03-12.sql.gz 
-rw-r--r-- 1 root root 186470 Mar 12 10:01 /opt/back/mysqlback_2020-03-12.sql.gz

[root@cots3 ~]# mysqldump -uroot -p --events -F -B data | gzip > /opt/back/mysqlbak_$(date +%F).sql.gz #备份单个库
Enter password: 

 

#增量备份

增量备份就是上一次全量备份之后,到下一次全备的中间的备份就是增量备份

#企业场景全量备份和增量备份部署

1.中小公司,全量一般是每天一次,业务流量低估执行全备,备份时会锁表
#按天备份的优缺点
优点:恢复时间短,维护成本低
缺点:占用空间多,占用系统资源多,经常锁表影响用户体验

2.大公司周备,每周六00点一次全量,下周日-下周六00点前都是增量
#按周备份的优缺点
优点:占用空间小,占用系统资源少,无需锁表,用户体验好点
缺点:维护成本高,恢复麻烦,时间长

 

#增量恢复

利用二进制日志binlog和全备进行的恢复过程,称为增量恢复

#增量恢复的应用场景

1.人为操作数据库SQL语句破坏主库
2.只有一个主库

#增量恢复的必要条件

#开启MySQL的log-bin日志功能

/etc/my.cnf
[mysqld]
log_bin=mysql_bin
server-id=1

 

7.使用mysqlbinlog来增量恢复

#增量恢复主要是靠binlog日志来进行恢复

#mysqlbinlog是用来解析mysql的binlog日志的

#mysqlbinlog的日志作用:用来记录MySQL内部增删改查等对MySQL数据库有更新的内容的记录

#提示:查看binlog日志需要使用mysqlbinlog打开

[root@ctos3 data]# mysqlbinlog mysql_bin.000001 
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=1*/;
/*!50003 SET @OLD_COMPLETION_TYPE=@@COMPLETION_TYPE,COMPLETION_TYPE=0*/;
DELIMITER /*!*/;
# at 4
#200313  8:31:31 server id 1  end_log_pos 123 CRC32 0x9ffc5808     Start: binlog v 4, server v 5.7.29-log created 200313  8:31:31 at startup
# Warning: this binlog is either in use or was not closed properly.
ROLLBACK/*!*/;
BINLOG '
I31rXg8BAAAAdwAAAHsAAAABAAQANS43LjI5LWxvZwAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA
AAAAAAAAAAAAAAAAAAAjfWteEzgNAAgAEgAEBAQEEgAAXwAEGggAAAAICAgCAAAACgoKKioAEjQA
AQhY/J8=
'/*!*/;
# at 123
#200313  8:31:31 server id 1  end_log_pos 154 CRC32 0x2f9f0a63     Previous-GTIDs
# [empty]
# at 154
#200313  8:40:27 server id 1  end_log_pos 219 CRC32 0x49d233b5     Anonymous_GTID    last_committed=0    sequence_number=1    rbr_only=no
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 219
#200313  8:40:27 server id 1  end_log_pos 313 CRC32 0x163c2e24     Query    thread_id=3    exec_time=0    error_code=0
SET TIMESTAMP=1584103227/*!*/;
SET @@session.pseudo_thread_id=3/*!*/;
SET @@session.foreign_key_checks=1, @@session.sql_auto_is_null=0, @@session.unique_checks=1, @@session.autocommit=1/*!*/;
SET @@session.sql_mode=32/*!*/;
SET @@session.auto_increment_increment=1, @@session.auto_increment_offset=1/*!*/;
/*!\C utf8 *//*!*/;
SET @@session.character_set_client=33,@@session.collation_connection=33,@@session.collation_server=33/*!*/;
SET @@session.lc_time_names=0/*!*/;
SET @@session.collation_database=DEFAULT/*!*/;
create database data
/*!*/;
# at 313
#200313  8:40:32 server id 1  end_log_pos 378 CRC32 0x404f0c1d     Anonymous_GTID    last_committed=1    sequence_number=2    rbr_only=no
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 378
#200313  8:40:32 server id 1  end_log_pos 466 CRC32 0xfcb07e1f     Query    thread_id=3    exec_time=0    error_code=0
SET TIMESTAMP=1584103232/*!*/;
create database db
/*!*/;
# at 466
#200313  8:41:11 server id 1  end_log_pos 531 CRC32 0xb1d1de3b     Anonymous_GTID    last_committed=2    sequence_number=3    rbr_only=no
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 531
#200313  8:41:11 server id 1  end_log_pos 726 CRC32 0x9dbf88b2     Query    thread_id=3    exec_time=0    error_code=0
use `data`/*!*/;
SET TIMESTAMP=1584103271/*!*/;
create table test (
id int(4) not null auto_increment,
name char(20) not null,
age varchar(16) not null,
primary key(id))
/*!*/;
# at 726
#200313  8:41:32 server id 1  end_log_pos 791 CRC32 0x44340287     Anonymous_GTID    last_committed=3    sequence_number=4    rbr_only=yes
/*!50718 SET TRANSACTION ISOLATION LEVEL READ COMMITTED*//*!*/;
SET @@SESSION.GTID_NEXT= 'ANONYMOUS'/*!*/;
# at 791
#200313  8:41:32 server id 1  end_log_pos 863 CRC32 0xea8b7d1b     Query    thread_id=3    exec_time=0    error_code=0
SET TIMESTAMP=1584103292/*!*/;
BEGIN
/*!*/;
# at 863
#200313  8:41:32 server id 1  end_log_pos 916 CRC32 0x8bc89c48     Table_map: `data`.`test` mapped to number 108
# at 916
#200313  8:41:32 server id 1  end_log_pos 981 CRC32 0xbccabc0a     Write_rows: table id 108 flags: STMT_END_F

BINLOG '
fH9rXhMBAAAANQAAAJQDAAAAAGwAAAAAAAEABGRhdGEABHRlc3QAAwP+DwT+PDAAAEicyIs=
fH9rXh4BAAAAQQAAANUDAAAAAGwAAAAAAAEAAgAD//gBAAAACHpoYW5nc2FuAjE5+AIAAAAEbGlz
aQIyMAq8yrw=
'/*!*/;
# at 981
#200313  8:41:32 server id 1  end_log_pos 1012 CRC32 0x24abc81e     Xid = 13
COMMIT/*!*/;
SET @@SESSION.GTID_NEXT= 'AUTOMATIC' /* added by mysqlbinlog */ /*!*/;
DELIMITER ;
# End of log file
/*!50003 SET COMPLETION_TYPE=@OLD_COMPLETION_TYPE*/;
/*!50530 SET @@SESSION.PSEUDO_SLAVE_MODE=0*/;
mysqlbinlog

 

#恢复方法

#1.基于位置点的增量恢复

[root@ctos3 data]# pwd
/application/mysql/data
[root@ctos3 data]# ls -l | grep bin
-rw-r-----. 1 mysql mysql     1035 Mar 13 08:44 mysql_bin.000001
-rw-r-----. 1 mysql mysql      154 Mar 13 08:44 mysql_bin.000002
-rw-r-----. 1 mysql mysql       38 Mar 13 08:44 mysql_bin.index
    
#指定开始位置到结束位置,从pos466开始到531结束
[root@ctos3 data]# mysqlbinlog --no-defaults mysql_bin.000001 --start-position=466 --stop-position=531 -r pos.sql
[root@ctos3 data]# ls -l | grep pos.sql
-rw-r-----. 1 root  root       936 Mar 13 08:47 pos.sql

#指定开始位置到文件结束
[root@ctos3 data]# mysqlbinlog  --no-defaults mysql_bin.000001 --start-position=531 -r pos531-end.sql
[root@ctos3 data]# ls -l | grep 531
-rw-r-----. 1 root  root      2450 Mar 13 08:49 pos531-end.sql

#从文件开头到指定位置结束
#提示:关键参数为at,指定开始和结束的位置

 

#2.指定时间来恢复

[root@ctos3 data]# mysqlbinlog  --no-defaults  mysql-bin.000001 --start-datetime='2020-1-22  17:30:40' --stop-datetime='2020-3-22 17:30:58' -r time.sql

 

8.生产场景不同引擎备份命令

#企业生产场景不同引擎备份命令

#myisam

[root@ctos3 ~]# mysqldump -uroot -p -A -B --master-data=2 -x --events | gzip > /opt/all.sql.gz 

#innodb

[root@ctos3 ~]# mysqldump -uroot -p -A -B --master-data=2 --events --single-transaction | gzip > /opt/all_1.sql.gz

 

原文出处:https://www.cnblogs.com/guoke-boy/p/12458249.html

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