MySQL development: Sharing experience in data backup and recovery projects

MySQL is currently one of the most popular relational database management systems. It is widely used in various fields such as the Internet, finance, and logistics. It not only has high reliability and stability, but also There are also better data storage and management capabilities. In daily development work, data backup and recovery are an essential part. The following is some of my experience sharing in actual project development.

1. The importance of data backup

Data backup is one of the important means to ensure database security. Once data is lost, it will have a huge impact on the operation and management of the enterprise. Therefore, developers should fully realize the importance of data backup and take appropriate measures to perform backup.

2. Selection of data backup solutions

MySQL provides a variety of backup solutions, including mysqldump, physical backup (based on file system), binary log backup, etc. The following is the backup solution I have used.

1. mysqldump backup

mysqldump is MySQL’s own backup tool that can completely back up the database in SQL format. When using this backup plan, you need to set the following parameters:

(1) Back up the database

mysqldump -u root -p --opt database_name > backup_file.sql

(2) Back up only a certain table

mysqldump -u root -p database_name table_name > backup_file.sql

The advantage of mysqldump backup is that The file takes up little space and is highly readable, but the disadvantage is that the backup speed is slow and the backup time is long. For large database backups, volume backup may be required.

2. Physical backup

Physical backup refers to backing up MySQL data files and backing up at the data file level. The backup process includes two parts: copy of data files and backup of binary logs. When using this backup solution, you need to use tools such as rsync and scp to copy the data files to the backup server.

The advantage of physical backup is that the backup speed is fast and the backup time is short, but the disadvantage is that the backup file takes up relatively large space.

3. Binary log backup

MySQL’s binary log records all changes made to the database. When using this backup plan, you only need to back up the binary log. When using this backup plan, you need to set the following parameters:

(1) Enable binary log

log-bin=mysql-bin

(2) Back up binary log

mysqlbinlog -u root -p binlog_file > backup_file.sql

The advantage of binary log backup is that It is fast and can perform incremental backup and differential backup, but the disadvantage is that the backup file cannot be directly used to restore data, and the binary log needs to be parsed first.

3. Selection of data recovery plan

Before data recovery, you need to decide which backup plan to use for recovery. The following is the data recovery solution I have used.

1. mysqldump recovery

When using mysqldump for backup, you can use the following command to restore:

mysql -u root -p database_name < backup_file.sql

This command will import the data in the backup file to in the specified database. Since the backup file is more readable, the backup file can be modified, such as deleting some records or adding some SQL statements.

2. Physical backup recovery

When using physical backup for backup, you can use the following command to restore:

(1) Stop MySQL

service mysql stop

(2) Copy the data file

Copy the backup file to the same path of the original server, overwriting the original data file.

(3) Start MySQL

service mysql start

When using physical backup for recovery, please note: before recovery, you need to stop the MySQL service; after recovery, you need to restart the MySQL service; large database recovery Sometimes, multiple backups and volume backups may be required.

3. Binary log recovery

When using binary logs for backup, you can use the following command to restore:

(1) Restore the data before the recovery time point Copy the binary log to the backup server

(2) Use the mysqlbinlog command to parse the binary log

mysqlbinlog -u root -p --start_datetime="2019-01-01 00:00:00" --stop_datetime="2019-01-02 00:00:00" mysql-bin.000001 > backup_file.sql

(3) Import the generated SQL file into the specified database

mysql -u root -p database_name < backup_file.sql

Use binary When restoring logs, you need to pay attention to: the recovery time point needs to be accurately determined; for large databases, multiple backups and restores may be required.

4. Frequently asked questions about data backup and recovery

In the actual backup and recovery process, you may encounter some problems. Here are some common problems and their solutions.

1. The backup file is too large

To solve the problem of the backup file being too large, you can use volume backup to solve the problem.

2. An error occurred during the recovery process

In response to the problem of recovery errors, you can print out the error log to view it, or extract some backup files for recovery.

3. Data Inconsistency

During the data recovery process, data inconsistency may occur. In this case, you can use the mysqldiff tool to compare the two databases, and then use the difference file to make modifications.

5. Summary

Data backup and recovery are an essential part of MySQL development work. Developers should fully realize the importance of data backup and choose appropriate backup and recovery solutions. At the same time, corresponding solutions need to be developed for common problems to ensure the security and reliability of the database.

The above is the detailed content of MySQL development: Sharing experience in data backup and recovery projects. For more information, please follow other related articles on the PHP Chinese website!