bitsCN.com
前言:
随着innodb的普及,innobackup也成为了主流备份方式。物理备份对于新建slave,全库恢复的需求都能从容应对。
但当面临单表数据误删,或者单表误drop的情况,如果使用物理全备进行恢复呢?
下文将进行详细分析。
恢复过程中需要用到的工具,percona data recover tool : https://launchpad.net/percona-innodb-recovery-tool
情况一:误删部分数据,需要用最近一次备份覆盖
来自同一台机器的ibd恢复覆盖,且备份后table没有被recreate过。
这种情况是最简单的,备份时的ibd文件(后称老ibd)中的space id和index id 与 新ibd的space id 和index id一致。
且和ibdata文件中的space id和index id一致。因此,物理文件可以直接覆盖做恢复。
以下是详细步骤
Step -1 : 物理备份
innobackupex --defaults-file=/usr/local/mysql3321/my.cnf --socket=/xfs/mysql3321/mysql.sock --user=root --password=password /xfs/backup/
Step 0 : apply log
innobackupex --apply-log --defaults-file=/usr/local/mysql3321/my.cnf /xfs/backup/2012-10-17_11-29-20/
Step 1 : 备份现在的ibd文件(可选)
cp -a testibd.ibd testibd.bak
Step 2 : 舍弃现在ibd文件
mysql> alter table testibd discard tablespace
Step 3 : 复制备份ibd文件
shell> cp /xfs/backup/2012-10-17_11-29-20/test/testibd.ibd /xfs/mysql3321/test/
shell> chown mysql:mysql /xfs/mysql3321/test/testibd.ibd
Step 4 : 导入ibd文件
mysql> alter table testibd import tablespace
情况二:误删 table,表结构已经被drop了
这种情况稍复杂,不过恢复过程还是比较容易操作的。由于table被drop后的space id会留空因此备份文件的space id不会被占用。
我们只需要重建表结构,然后把ibdata中该表的space id还原,物理文件可以直接覆盖做恢复了。
Step 1 : 重建表
mysql> create table testibd (UserID int);
Step 2 : 关闭mysql服务(必须)
shell> service mysqld3321 stop
Step 3: 准备ibd文件 apply log
shell> innobackupex --apply-log --defaults-file=/usr/local/mysql3321/my.cnf /xfs/backup/2012-10-17_11-29-20/
Step 4 : 备份现在的ibd文件(可选)
cp -a testibd.ibd testibd.bak
Step 5 : 复制备份ibd文件
shell> cp -a /xfs/backup/2012-10-17_11-29-20/test/testibd.ibd /xfs/mysql3321/test/
shell> chown mysql:mysql /xfs/mysql3321/test/testibd.ibd
Step 6 : 使用percona recovery tool 修改ibdata
shell> /root/install/percona-data-recovery-tool-for-innodb-0.5/ibdconnect -o /xfs/mysql3321/ibdata1 -f /xfs/mysql3321/test/testibd.ibd -d test -t testibd


Initializing table definitions...Processing table: SYS_TABLES - total fields: 10 - nullable fields: 6 - minimum header size: 5 - minimum rec size: 21 - maximum rec size: 555Processing table: SYS_INDEXES - total fields: 9 - nullable fields: 5 - minimum header size: 5 - minimum rec size: 29 - maximum rec size: 165Setting SPACE=1 in SYS_TABLE for `test`.`testibd`Check if space id 1 is already usedPage_id: 8, next page_id: 4294967295Record position: 65Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 8 50 3 2 0 0 0 0 0 Db/table: infimumSpace id: 1768842857 (0x696E6669)Next record at offset: 8DRecord position: 8DChecking field lengths for a row (SYS_TABLES): OFFSETS: 16 11 17 24 32 36 40 48 52 52 Db/table: SYS_FOREIGNSpace id: 0 (0x0)Next record at offset: D5Record position: D5Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 16 22 29 37 41 45 53 57 57 Db/table: SYS_FOREIGN_COLSSpace id: 0 (0x0)Next record at offset: 122Record position: 122Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 12 18 25 33 37 41 49 53 53 Db/table: test/testibdSpace id: 2 (0x2)Next record at offset: 74Space id 1 is not used in any of the records in SYS_TABLESPage_id: 8, next page_id: 4294967295Record position: 65Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 8 50 3 2 0 0 0 0 0 Db/table: infimumSpace id: 1768842857 (0x696E6669)Next record at offset: 8DRecord position: 8DChecking field lengths for a row (SYS_TABLES): OFFSETS: 16 11 17 24 32 36 40 48 52 52 Db/table: SYS_FOREIGNSpace id: 0 (0x0)Next record at offset: D5Record position: D5Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 16 22 29 37 41 45 53 57 57 Db/table: SYS_FOREIGN_COLSSpace id: 0 (0x0)Next record at offset: 122Record position: 122Checking field lengths for a row (SYS_TABLES): OFFSETS: 16 12 18 25 33 37 41 49 53 53 Db/table: test/testibdSpace id: 2 (0x2)Updating test/testibd (table_id 17) with id 0x01000000SYS_TABLES is updated successfullyInitializing table definitions...Processing table: SYS_TABLES - total fields: 10 - nullable fields: 6 - minimum header size: 5 - minimum rec size: 21 - maximum rec size: 555Processing table: SYS_INDEXES - total fields: 9 - nullable fields: 5 - minimum header size: 5 - minimum rec size: 29 - maximum rec size: 165Setting SPACE=1 in SYS_INDEXES for TABLE_ID = 17Page_id: 11, next page_id: 4294967295Record position: 65Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 50 7 2 0 0 0 0 TABLE_ID: 3798561113125514496SPACE: 1768842857Next record at offset: 8CRecord position: 8CChecking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 35 39 43 47 TABLE_ID: 11SPACE: 0Next record at offset: CERecord position: CEChecking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 36 40 44 48 TABLE_ID: 11SPACE: 0Next record at offset: 111Record position: 111Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 36 40 44 48 TABLE_ID: 11SPACE: 0Next record at offset: 154Record position: 154Checking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 35 39 43 47 TABLE_ID: 12SPACE: 0Next record at offset: 22CRecord position: 22CChecking field lengths for a row (SYS_INDEXES): OFFSETS: 15 8 16 22 29 44 48 52 56 TABLE_ID: 17SPACE: 2Updating SPACE(0x00000001 , 0x01000000) for TABLE_ID: 17sizeof(s)=4Next record at offset: 74SYS_INDEXES is updated successfully
Step 7 : 使用percona recovery tool 重新checksum ibdata
重复执行以下命令,直到程序没有输出为止。
shell> /root/install/percona-data-recovery-tool-for-innodb-0.5/innochecksum -f /xfs/mysql3321/ibdata1


page 8 invalid (fails old style checksum)page 8: old style: calculated = 0xF4AD74CB; recorded = 0xEECB309Dfixing old checksum of page 8page 8 invalid (fails new style checksum)page 8: new style: calculated = 0x6F0C29B4; recorded = 0x3D02308Cfixing new checksum of page 8page 11 invalid (fails old style checksum)page 11: old style: calculated = 0x3908087C; recorded = 0xF9E8D30Cfixing old checksum of page 11page 11 invalid (fails new style checksum)page 11: new style: calculated = 0xB26CFD77; recorded = 0xDB25D39Dfixing new checksum of page 11
Step 8 : 启动mysql服务
shell> service mysqld3321 start
参考文档:
http://www.chriscalender.com/?p=28
http://www.mysqlperformanceblog.com/2011/05/13/connecting-orphaned-ibd-files/
http://blogs.innodb.com/wp/2012/04/innodb-transportable-tablespaces/
bitsCN.com

InnoDBBufferPool reduces disk I/O by caching data and indexing pages, improving database performance. Its working principle includes: 1. Data reading: Read data from BufferPool; 2. Data writing: After modifying the data, write to BufferPool and refresh it to disk regularly; 3. Cache management: Use the LRU algorithm to manage cache pages; 4. Reading mechanism: Load adjacent data pages in advance. By sizing the BufferPool and using multiple instances, database performance can be optimized.

Compared with other programming languages, MySQL is mainly used to store and manage data, while other languages such as Python, Java, and C are used for logical processing and application development. MySQL is known for its high performance, scalability and cross-platform support, suitable for data management needs, while other languages have advantages in their respective fields such as data analytics, enterprise applications, and system programming.

MySQL is worth learning because it is a powerful open source database management system suitable for data storage, management and analysis. 1) MySQL is a relational database that uses SQL to operate data and is suitable for structured data management. 2) The SQL language is the key to interacting with MySQL and supports CRUD operations. 3) The working principle of MySQL includes client/server architecture, storage engine and query optimizer. 4) Basic usage includes creating databases and tables, and advanced usage involves joining tables using JOIN. 5) Common errors include syntax errors and permission issues, and debugging skills include checking syntax and using EXPLAIN commands. 6) Performance optimization involves the use of indexes, optimization of SQL statements and regular maintenance of databases.

MySQL is suitable for beginners to learn database skills. 1. Install MySQL server and client tools. 2. Understand basic SQL queries, such as SELECT. 3. Master data operations: create tables, insert, update, and delete data. 4. Learn advanced skills: subquery and window functions. 5. Debugging and optimization: Check syntax, use indexes, avoid SELECT*, and use LIMIT.

MySQL efficiently manages structured data through table structure and SQL query, and implements inter-table relationships through foreign keys. 1. Define the data format and type when creating a table. 2. Use foreign keys to establish relationships between tables. 3. Improve performance through indexing and query optimization. 4. Regularly backup and monitor databases to ensure data security and performance optimization.

MySQL is an open source relational database management system that is widely used in Web development. Its key features include: 1. Supports multiple storage engines, such as InnoDB and MyISAM, suitable for different scenarios; 2. Provides master-slave replication functions to facilitate load balancing and data backup; 3. Improve query efficiency through query optimization and index use.

SQL is used to interact with MySQL database to realize data addition, deletion, modification, inspection and database design. 1) SQL performs data operations through SELECT, INSERT, UPDATE, DELETE statements; 2) Use CREATE, ALTER, DROP statements for database design and management; 3) Complex queries and data analysis are implemented through SQL to improve business decision-making efficiency.

The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA


Hot AI Tools

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Undress AI Tool
Undress images for free

Clothoff.io
AI clothes remover

AI Hentai Generator
Generate AI Hentai for free.

Hot Article

Hot Tools

Dreamweaver Mac version
Visual web development tools

mPDF
mPDF is a PHP library that can generate PDF files from UTF-8 encoded HTML. The original author, Ian Back, wrote mPDF to output PDF files "on the fly" from his website and handle different languages. It is slower than original scripts like HTML2FPDF and produces larger files when using Unicode fonts, but supports CSS styles etc. and has a lot of enhancements. Supports almost all languages, including RTL (Arabic and Hebrew) and CJK (Chinese, Japanese and Korean). Supports nested block-level elements (such as P, DIV),

SublimeText3 Chinese version
Chinese version, very easy to use

WebStorm Mac version
Useful JavaScript development tools

MinGW - Minimalist GNU for Windows
This project is in the process of being migrated to osdn.net/projects/mingw, you can continue to follow us there. MinGW: A native Windows port of the GNU Compiler Collection (GCC), freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All MinGW software can run on 64-bit Windows platforms.