一、场景说明：
很多时候因为 MySQL 数据库不能启动而造成数据无法访问，但应用的数据通常没有丢失，只是系统表空间等其它文件损坏了，或者遇到 MySQL 的 bug。
这个时候如果没有备份，很多人就以为数据丢失了，但实际上大部分时候数据还是有救的。
对于 MyISAM 引擎的表空间，直接把对应的数据文件拷贝到一个新的数据库就行了，数据就可以恢复了。
对于 InnoDB 引擎的数据库表空间可以采用传输表空间的方式把数据救回来.
前提是MySQL开启了参数 innodb_file_per_table = 1 独立表空间文件
当MySQL的数据表空间文件ibdata文件损坏或者是被无修改和删除，导致MySQL服务重启失败。同时MySQL的数据又没有及时备份，此时如何尽可能多的找回MySQL数据呢？？
二、案例演示：
2.1、确认MySQL故障前，库中的每张表有多少记录
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for n in `mysql -e "use db_bbs;show tables;"|sed '1d'`;do echo $n; mysql -e "use db_bbs;select count(*) from $n;";done >test.txt
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确认MySQL故障前，库中一共有多少张表：
一共是39张表：
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[root@10-10-127-11 ~]# mysql -e "use db_bbs;show tables;"|sed '1d'|wc -l
39
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2.2、模拟删除ibdata故障：
删除ibdata文件（生产环境禁止这么干）
innodb_force_recovery =6 利用MySQL的强制启动参数来启动此时的MySQL服务，但是已经是无济于事。由于是数据表空间文件ibdata文件被删除了.所以启动不了此时的MySQL服务。
由于此MySQL采用的innodb引擎。而且开启了独立表空间参数 innodb_file_per_table = 1 。所以此时可以采用采用传输表空间的方式把数据救回来。
2.3、找回数据的办法:
首先来创建已经丢失的表结构：
先要在故障的MySQL服务器上 安装 mysql-utilities。
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yum -y install mysql-utilities
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使用 mysqlfrm 从 .frm 文件里面找回建表语句:
分析一个 .frm 文件生成建表的语句
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mysqlfrm --diagnostic
[root@test02 db_bbs]# mysqlfrm --diagnostic /data/mysql/data/db_bbs/t_admin.frm |grep -v "^#"
CREATE TABLE `db_bbs`.`t_admin` (
`f_id` int(4) NOT NULL AUTO_INCREMENT,
`f_type` tinyint(1) NOT NULL,
`f_username` varchar(80) NOT NULL,
`f_password` varchar(80) NOT NULL,
`f_nick_name` varchar(80) NOT NULL,
`f_real_name` varchar(80) NOT NULL,
`f_create_time` bigint(4) NOT NULL,
`f_update_time` bigint(4) NOT NULL,
`f_last_login_time` bigint(4) DEFAULT NULL,
`f_last_login_ip` varchar(80) DEFAULT NULL,
`f_status` tinyint(1) NOT NULL,
PRIMARY KEY `PRIMARY` (`f_id`) USING BTREE
) ENGINE=InnoDB ROW_FORMAT = 2;
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把全部的建表语句导入到/tmp/create.sql 文件：
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[root@test02 ~]# cd /data/mysql/data/db_bbs/
[root@test02 db_bbs]# for n in `ls -l /data/mysql/data/db_bbs/*.frm|awk -F '/' '{print $NF}'|xargs -n 40`;do mysqlfrm --diagnostic $n|grep -v "^#" >>/tmp/create.sql;done
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把生产的建表语句导入到新MySQL实例库中:
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[root@10-10-127-11 ~]# mysql db_bbs < create.sql
ERROR 1064 (42000) at line 2: 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 '5' at line 10
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原因是获取到的建表sql中包含了ROW_FORMAT = 2 这样的参数导致的
###去掉建表语句中的包含ROW_FORMAT = 2, ROW_FORMAT = 5这些字符.重新导入建表语句###
批量替换命令如下:
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cat /tmp/create.sql|sed -e 's/ENGINE=InnoDB ROW_FORMAT = 2;/ENGINE=InnoDB ;/g'|grep ROW_FORMAT |uniq -c
cat /tmp/create.sql|sed -e 's/ENGINE=InnoDB ROW_FORMAT = 5;/ENGINE=InnoDB ;/g'|grep ROW_FORMAT |uniq -c
sed -i 's/ENGINE=InnoDB ROW_FORMAT = 2;/ENGINE=InnoDB ;/g' /tmp/create.sql
sed -i 's/ENGINE=InnoDB ROW_FORMAT = 5;/ENGINE=InnoDB ;/g' /tmp/create.sql
cat /tmp/create.sql|grep ROW_FORMAT |uniq -c
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导出建表语句到新MySQL实例db_bbs库报错字段太长：
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[root@10-10-127-11 ~]# mysql db_bbs -f < create.sql
ERROR 1074 (42000) at line 232: Column length too big for column 'f_content' (max = 16383); use BLOB or TEXT instead
ERROR 1074 (42000) at line 299: Column length too big for column 'f_desc' (max = 16383); use BLOB or TEXT instead
ERROR 1074 (42000) at line 365: Column length too big for column 'f_body_image' (max = 16383); use BLOB or TEXT instead
ERROR 1074 (42000) at line 406: Column length too big for column 'f_content' (max = 16383); use BLOB or TEXT instead
ERROR 1074 (42000) at line 433: Column length too big for column 'f_summary' (max = 16383); use BLOB or TEXT instead
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修改完字段长度类型，重新导入建表sql到全新的MySQL库中
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[root@10-10-127-11 ~]# mysql db_bbs -f < create.sql
[root@10-10-127-11 ~]#
[root@10-10-127-11 ~]#
[root@10-10-127-11 ~]# mysql -e "use db_bbs;show tables;"|sed '1d'|wc -l
39
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###将新建的MySQL实例的 没有包括数据的 .ibd 文件抛弃掉，然后再导入故障数据库的.idb文件###
抛弃掉新建库的数据.ibd文件：
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mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a DISCARD TABLESPACE" ;done
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[root@10-10-127-11 db_bbs]# ll *.ibd|wc -l
39
[root@10-10-127-11 db_bbs]# mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a DISCARD TABLESPACE" ;done
[root@10-10-127-11 db_bbs]# ll *.ibd|wc -l
ls: cannot access *.ibd: No such file or directory
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*可以看到所有的 .idb 文件都已经被抛弃了。然后把旧的有数据的 .ibd 文件拷贝到这个新MySQL实例的 ./data/db_bbs/ 目录下面，别忘了把属主改过来：chown mysql. ，再把这些数据文件 import 到数据库中**。
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[root@test02 db_bbs]# scp *.ibd root@10.10.127.11:/data/mysql/data/db_bbs/
root@10.10.127.11's password:
browse_record.ibd 100% 100MB 50.0MB/s 00:02
t_admin.ibd
........
........
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[root@10-10-127-11 db_bbs]# ll *.ibd|wc -l
39
[root@10-10-127-11 db_bbs]# ll *.ibd
-rw-r----- 1 root root 104857600 Mar 14 21:56 browse_record.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_admin.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_anonymous_code.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_apply.ibd
-rw-r----- 1 root root 9437184 Mar 14 21:56 t_attach.ibd
-rw-r----- 1 root root 147456 Mar 14 21:56 t_banner.ibd
-rw-r----- 1 root root 163840 Mar 14 21:56 t_banner_log.ibd
-rw-r----- 1 root root 114688 Mar 14 21:56 t_black_ip.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_black_user.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_block_userbaseinfo.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_collect.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_country_code.ibd
-rw-r----- 1 root root 163840 Mar 14 21:56 t_ct_goods.ibd
-rw-r----- 1 root root 131072 Mar 14 21:56 t_ct_goods_record.ibd
-rw-r----- 1 root root 9437184 Mar 14 21:56 t_ct_integral.ibd
-rw-r----- 1 root root 46137344 Mar 14 21:56 t_ct_integral_record.ibd
-rw-r----- 1 root root 27262976 Mar 14 21:56 t_ct_news.ibd
-rw-r----- 1 root root 9437184 Mar 14 21:56 t_ct_order.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_feedback.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_lexicon.ibd
-rw-r----- 1 root root 327680 Mar 14 21:56 t_logs.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_manage.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_module.ibd
-rw-r----- 1 root root 9437184 Mar 14 21:56 t_post_extend.ibd
-rw-r----- 1 root root 12582912 Mar 14 21:56 t_post.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_post_video.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_realtime_message.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_recommend.ibd
-rw-r----- 1 root root 46137344 Mar 14 21:56 t_reply.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_reward.ibd
-rw-r----- 1 root root 196608 Mar 14 21:56 t_sensitive_word.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_system_message.ibd
-rw-r----- 1 root root 9437184 Mar 14 21:56 t_userbaseinfo.ibd
-rw-r----- 1 root root 344064 Mar 14 21:56 t_userextendinfo.ibd
-rw-r----- 1 root root 12582912 Mar 14 21:56 t_user_health.ibd
-rw-r----- 1 root root 98304 Mar 14 21:56 t_user_message.ibd
-rw-r----- 1 root root 442368 Mar 14 21:56 t_user_read_module_log.ibd
-rw-r----- 1 root root 17825792 Mar 14 21:56 t_viewpoint.ibd
-rw-r----- 1 root root 114688 Mar 14 21:56 t_white_ip.ibd
[root@10-10-127-11 db_bbs]# chown mysql.mysql *.ibd
mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a import TABLESPACE" ;done
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导入每个表的表空间时，出现个别表报错：
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[root@10-10-127-11 db_bbs]# mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a import TABLESPACE" ;done
ERROR 1808 (HY000) at line 1: Schema mismatch (Table has ROW_TYPE_DYNAMIC row format, .ibd file has ROW_TYPE_COMPACT row format.)
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校验表文件，发现只有browse_record表导入独立表表空间时报错导致此表恢复数据失败
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[root@10-10-127-11 db_bbs]# mysqlcheck -c db_bbs
db_bbs.browse_record
Warning : InnoDB: Tablespace has been discarded for table 'browse_record'
Error : Tablespace has been discarded for table 'browse_record'
error : Corrupt
db_bbs.t_admin OK
db_bbs.t_anonymous_code OK
db_bbs.t_apply OK
db_bbs.t_attach OK
db_bbs.t_banner OK
db_bbs.t_banner_log OK
db_bbs.t_black_ip OK
db_bbs.t_black_user OK
db_bbs.t_block_userbaseinfo OK
db_bbs.t_collect OK
db_bbs.t_country_code OK
db_bbs.t_ct_goods OK
db_bbs.t_ct_goods_record OK
db_bbs.t_ct_integral OK
db_bbs.t_ct_integral_record OK
db_bbs.t_ct_news OK
db_bbs.t_ct_order OK
db_bbs.t_feedback OK
db_bbs.t_lexicon OK
db_bbs.t_logs OK
db_bbs.t_manage OK
db_bbs.t_module OK
db_bbs.t_post OK
db_bbs.t_post_extend OK
db_bbs.t_post_video OK
db_bbs.t_realtime_message OK
db_bbs.t_recommend OK
db_bbs.t_reply OK
db_bbs.t_reward OK
db_bbs.t_sensitive_word OK
db_bbs.t_system_message OK
db_bbs.t_user_health OK
db_bbs.t_user_message OK
db_bbs.t_user_read_module_log OK
db_bbs.t_userbaseinfo OK
db_bbs.t_userextendinfo OK
db_bbs.t_viewpoint OK
db_bbs.t_white_ip OK
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上面的browse_record 表恢复失败 报错解决办法如下：
参考：https://blog.csdn.net/weixin_30607659/article/details/94987901
删除导入到新MySQL实例的表browse_record，然后执行下面的建表语句，新建browse_record表：
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CREATE TABLE `browse_record` (
`id` int(4) unsigned NOT NULL AUTO_INCREMENT,
`post_id` int(4) unsigned NOT NULL,
`user_id` int(4) unsigned NOT NULL,
`status` tinyint(1) unsigned NOT NULL,
`update_time` bigint(4) unsigned NOT NULL,
`create_time` bigint(4) unsigned NOT NULL,
PRIMARY KEY (`id`) USING BTREE,
KEY `browse` (`post_id`,`user_id`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 row_format=compact;
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提示：如果在新MySQL实例单独删除表browse_record，删除失败的话，那就直接drop掉新MySQL实例上的db_bbs库，重新导入db_bbs所有表的建表语句，然后再执行下面的命令：
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mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a DISCARD TABLESPACE" ;done
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重新导入表空间到新实例MySQL中:
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[root@10-10-127-11 db_bbs]# mysql -e "show tables from db_bbs" | grep -v Tables_in_db_bbs| while read a; do mysql -e "ALTER TABLE db_bbs.$a import TABLESPACE" ;done
[root@10-10-127-11 db_bbs]#
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到此处数据修复完成
校验MySQL db_bbs库中的表：
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[root@10-10-127-11 db_bbs]# mysqlcheck -c db_bbs
db_bbs.browse_record OK
db_bbs.t_admin OK
db_bbs.t_anonymous_code OK
db_bbs.t_apply OK
db_bbs.t_attach OK
db_bbs.t_banner OK
db_bbs.t_banner_log OK
db_bbs.t_black_ip OK
db_bbs.t_black_user OK
db_bbs.t_block_userbaseinfo OK
db_bbs.t_collect OK
db_bbs.t_country_code OK
db_bbs.t_ct_goods OK
db_bbs.t_ct_goods_record OK
db_bbs.t_ct_integral OK
db_bbs.t_ct_integral_record OK
db_bbs.t_ct_news OK
db_bbs.t_ct_order OK
db_bbs.t_feedback OK
db_bbs.t_lexicon OK
db_bbs.t_logs OK
db_bbs.t_manage OK
db_bbs.t_module OK
db_bbs.t_post OK
db_bbs.t_post_extend OK
db_bbs.t_post_video OK
db_bbs.t_realtime_message OK
db_bbs.t_recommend OK
db_bbs.t_reply OK
db_bbs.t_reward OK
db_bbs.t_sensitive_word OK
db_bbs.t_system_message OK
db_bbs.t_user_health OK
db_bbs.t_user_message OK
db_bbs.t_user_read_module_log OK
db_bbs.t_userbaseinfo OK
db_bbs.t_userextendinfo OK
db_bbs.t_viewpoint OK
db_bbs.t_white_ip OK
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2.4、获取导入到新MySQL实例db_bbs库中表记录和和原来的库test.txt表记录文件对比
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[root@10-10-127-11 ~]# for n in `mysql -e "use db_bbs;show tables;"|sed '1d'`;do echo $n; mysql -e "use db_bbs;select count(*) from $n;";done >test.txt11
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和原来的库test.txt表记录文件对比。
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[root@test02 ~]# vimdiff test.txt11 test.txt
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表记录完全一致
到此处MySQL的数据修复完毕
参考资料：
https://mp.weixin.qq.com/s/r3KTPsFay292JnO0lgTLUg
https://www.cnblogs.com/jiangxu67/p/4744283.html
https://blog.csdn.net/Sonny_alice/article/details/80198200
https://www.cnblogs.com/jiangxu67/p/4744283.html
到此这篇关于mysql5.7.33误删除ibdata文件找回数据的方法的文章就介绍到这了,更多相关mysql误删ibdata内容请搜索服务器之家以前的文章或继续浏览下面的相关文章希望大家以后多多支持服务器之家！
原文链接：https://blog.51cto.com/wujianwei/2665154