關于mysql數據庫誤刪除后的數據恢復操作的示例代碼分享

下面小編就為大家帶來一篇關于數據庫誤刪除后的數據恢復操作說明。小編覺得挺不錯的,現在就分享給大家,也給大家做個參考。一起跟隨小編過來看看吧

在日常運維工作中,對于mysql數據庫的備份是至關重要的!數據庫對于網站的重要性使得我們對mysql數據的管理不容有失!
然后,是人總難免會犯錯誤,說不定哪天大腦短路了來個誤操作把數據庫給刪除了,怎么辦???

下面,就mysql數據庫誤刪除后的恢復方案進行說明。

一、工作場景

(1)MySQL數據庫每晚12:00自動完全備份。
(2)某天早上上班,9點的時候,一同事犯暈drop了一個數據庫!
(3)需要緊急恢復!可利用備份的數據文件以及增量的binlog文件進行數據恢復。

二、數據恢復思路

(1)利用全備的sql文件中記錄的CHANGE MASTER語句,binlog文件及其位置點信息,找出binlog文件中增量的那部分。
(2)用mysqlbinlog命令將上述的binlog文件導出為sql文件,并剔除其中的drop語句
(3)通過全備文件和增量binlog文件的導出sql文件,就可以恢復到完整的數據。

三、實例說明

—————————————-
首先,要確保mysql開啟了binlog日志功能
在/etc/my.cnf文件里的[mysqld]區塊添加:
log-bin=mysql-bin
然后重啟mysql服務
—————————————-

(1)在ops庫下創建一張表customers

mysql>?use?ops;  mysql>?create?table?customers(  ->?id?int?not?null?auto_increment,  ->?name?char(20)?not?null,  ->?age?int?not?null,  ->?primary?key(id)  ->?)engine=InnoDB;  Query?OK,?0?rows?affected?(0.09?sec)    mysql>?show?tables;  +---------------+  |?Tables_in_ops?|  +---------------+  |?customers?|  +---------------+  1?row?in?set?(0.00?sec)    mysql>?desc?customers;  +-------+----------+------+-----+---------+----------------+  |?Field?|?Type?|?Null?|?Key?|?Default?|?Extra?|  +-------+----------+------+-----+---------+----------------+  |?id?|?int(11)?|?NO?|?PRI?|?NULL?|?auto_increment?|  |?name?|?char(20)?|?NO?|?|?NULL?|?|  |?age?|?int(11)?|?NO?|?|?NULL?|?|  +-------+----------+------+-----+---------+----------------+  3?rows?in?set?(0.02?sec)    mysql>?insert?into?customers?values(1,"wangbo","24");  Query?OK,?1?row?affected?(0.06?sec)    mysql>?insert?into?customers?values(2,"guohui","22");  Query?OK,?1?row?affected?(0.06?sec)    mysql>?insert?into?customers?values(3,"zhangheng","27");  Query?OK,?1?row?affected?(0.09?sec)    mysql>?select?*?from?customers;  +----+-----------+-----+  |?id?|?name?|?age?|  +----+-----------+-----+  |?1?|?wangbo?|?24?|  |?2?|?guohui?|?22?|  |?3?|?zhangheng?|?27?|  +----+-----------+-----+  3?rows?in?set?(0.00?sec)

(2)現在進行全備份

[root@vm-002?~]#?mysqldump?-uroot?-p?-B?-F?-R?-x?--master-data=2?ops|gzip?>/opt/backup/ops_$(date?+%F).sql.gz  Enter?password:?  [root@vm-002?~]#?ls?/opt/backup/ops_2016-09-25.sql.gz  -----------------

參數說明:

-B:指定數據庫
-F:刷新日志
-R:備份
-x:鎖表
–master-data:在備份語句里添加CHANGE MASTER語句以及binlog文件及位置點信息
—————–

(3)再次

mysql>?insert?into?customers?values(4,"liupeng","21");  Query?OK,?1?row?affected?(0.06?sec)    mysql>?insert?into?customers?values(5,"xiaoda","31");  Query?OK,?1?row?affected?(0.07?sec)    mysql>?insert?into?customers?values(6,"fuaiai","26");  Query?OK,?1?row?affected?(0.06?sec)    mysql>?select?*?from?customers;  +----+-----------+-----+  |?id?|?name?|?age?|  +----+-----------+-----+  |?1?|?wangbo?|?24?|  |?2?|?guohui?|?22?|  |?3?|?zhangheng?|?27?|  |?4?|?liupeng?|?21?|  |?5?|?xiaoda?|?31?|  |?6?|?fuaiai?|?26?|  +----+-----------+-----+  6?rows?in?set?(0.00?sec)

(4)此時誤操作,刪除了test數據庫

mysql>?drop?database?ops;  Query?OK,?1?row?affected?(0.04?sec)

此時,全備之后到誤操作時刻之間,用戶寫入的數據在binlog中,需要恢復出來!

(5) 查看全備之后新增的binlog文件

[root@vm-002?~]#?cd?/opt/backup/  [root@vm-002?backup]#?ls  ops_2016-09-25.sql.gz  [root@vm-002?backup]#?gzip?-d?ops_2016-09-25.sql.gz?  [root@vm-002?backup]#?ls  ops_2016-09-25.sql  [root@vm-002?backup]#?grep?CHANGE?ops_2016-09-25.sql?  --?CHANGE?MASTER?TO?MASTER_LOG_FILE='mysql-bin.000002',?MASTER_LOG_POS=106;

這是全備時刻的binlog文件位置
即mysql-bin.000002的106行,因此在該文件之前的binlog文件中的數據都已經包含在這個全備的sql文件中了

(6)移動binlog文件,并導出為sql文件,剔除其中的drop語句

查看mysql的數據存放目錄,有下面可知是在/var/lib/mysql下

[root@vm-002?backup]#?ps?-ef|grep?mysql  root?9272?1?0?01:43?pts/1?00:00:00?/bin/sh?/usr/bin/mysqld_safe?  --datadir=/var/lib/mysql?--socket=/var/lib/mysql/mysql.sock?--pid-file=/var/run/mysqld/mysqld.pid?--basedir=/usr?--user=mysql  mysql?9377?9272?0?01:43?pts/1?00:00:00?/usr/libexec/mysqld?--basedir=/usr?  --datadir=/var/lib/mysql?--user=mysql?--log-error=/var/log/mysqld.log?--pid-file=/var/run/mysqld/mysqld.pid?--socket=/var/lib/mysql/mysql.sock  [root@vm-002?backup]#?cd?/var/lib/mysql/  [root@vm-002?mysql]#?ls  ibdata1?ib_logfile0?ib_logfile1?mysql?mysql-bin.000001?mysql-bin.000002?mysql-bin.index?mysql.sock?test  [root@vm-002?mysql]#?cp?mysql-bin.000002?/opt/backup/

將binlog文件導出sql文件,并vim編輯它刪除其中的drop語句

[root@vm-002?backup]#?mysqlbinlog?-d?ops?mysql-bin.000002?>002bin.sql  [root@vm-002?backup]#?ls  002bin.sql?mysql-bin.000002?ops_2016-09-25.sql  [root@vm-002?backup]#?vim?002bin.sql?#刪除里面的drop語句

注意:

在恢復全備數據之前必須將該binlog文件移出,否則恢復過程中,會繼續寫入語句到binlog,最終導致增量恢復數據部分變得比較混亂

(7)恢復數據

[root@vm-002?backup]#?mysql?-uroot?-p?<p>查看數據庫,看看ops庫在不在</p><pre class="brush:sql;">mysql&gt;?show?databases;  +--------------------+  |?Database?|  +--------------------+  |?information_schema?|  |?mysql?|  |?ops?|  |?test?|  +--------------------+  4?rows?in?set?(0.00?sec)    mysql&gt;?use?ops;  Reading?table?information?for?completion?of?table?and?column?names  You?can?turn?off?this?feature?to?get?a?quicker?startup?with?-A    Database?changed  mysql&gt;?select?*?from?customers;  +----+-----------+-----+  |?id?|?name?|?age?|  +----+-----------+-----+  |?1?|?wangbo?|?0?|  |?2?|?guohui?|?0?|  |?3?|?zhangheng?|?0?|  +----+-----------+-----+  3?rows?in?set?(0.00?sec)

此時恢復了全備時刻的數據

接著,使用002bin.sql文件恢復全備時刻到刪除數據庫之間,新增的數據

[root@vm-002?backup]#?mysql?-uroot?-p?ops?<p>再次查看數據庫,發現全備份到刪除數據庫之間的那部分數據也恢復了!!</p><pre class="brush:sql;">mysql&gt;?select?*?from?customers;  +----+-----------+-----+  |?id?|?name?|?age?|  +----+-----------+-----+  |?1?|?wangbo?|?24?|  |?2?|?guohui?|?22?|  |?3?|?zhangheng?|?27?|  |?4?|?liupeng?|?21?|  |?5?|?xiaoda?|?31?|  |?6?|?fuaiai?|?26?|  +----+-----------+-----+  6?rows?in?set?(0.00?sec)

? 版權聲明
THE END
喜歡就支持一下吧
點贊15 分享