How to recover accidentally deleted mysql

MySQL is a powerful relational database management system that is widely used in various websites, corporate internal management systems, and other similar data application scenarios. However, when using MySQL, it is inevitable to encounter accidental deletion of data. When data is lost, the consequences are often very serious and seriously affect normal business operations. Therefore, how to recover MySQL database from accidental deletion of data has become a hot topic among various developers and administrators.

This article will discuss how to recover a MySQL database that has accidentally deleted data.

1. Reasons for accidentally deleting data

In the daily use of MySQL, the reasons for accidentally deleting data can be divided into the following categories:

1. Human error : The administrator accidentally deleted the data of a certain table, or performed a wrong operation, causing the data to be accidentally deleted.

2. Malware attacks: Malware can infect computer systems through viruses, Trojans, etc., tamper with database contents, or even directly delete database contents.

3. Hardware failure: Hard disk damage, server failure and other reasons may also cause data to be accidentally deleted.

The above are common reasons for accidentally deleting data, but no matter what the reason is, accidentally deleting data brings great pain to the business.

2. MySQL accidentally deleted data recovery method

After MySQL accidentally deletes data, you need to take immediate action and process the data reasonably to ensure that as much data as possible can be recovered. The following are some common accidentally deleted data recovery methods:

1. Binary log backup data recovery method

MySQL’s binary log, also called binlog, is a feature provided by MySQL for data recovery. recovery path in file format. Binary log is a kind of data that can record addition, modification, deletion and other operations, and can better perform data recovery after data damage.

The following are the specific steps to use the binary log recovery method:

Step 1: View the status and information of the binary log

Use the following command to view the current status and information of the binary log Related information:

mysqlbinlog --help

This command can view the configuration parameters related to the binary log.

Step 2: Check the time point of accidentally deleted data

Find the time point of accidentally deleted data according to the timeline, and record the relevant configuration information of the binary log.

Step 3: Create a new MySQL instance

You can restore accidentally deleted data by creating a new MySQL instance. The specific command is as follows:

mysqldump -h host name -u Username -p [password] --routines --triggers --create-options --single-transaction --master-data=2 dbname > dbname.sql

Note: This command can add the required The data is imported into the dbname.sql file to facilitate data backup.

Step 4: Perform the same operation as the backup

When restoring data, you can follow the operation of the most recent backup. If the accidentally deleted data has not been backed up after being backed up, you can skip this step and go directly to the next step.

Step 5: Use binary logs for data recovery

Take out the binary logs one by one according to the time of accidental deletion, and use the MySQL command line tool to modify them.

2. Rebuilding table method

In MySQL, if the contents of a table are accidentally deleted, but the table structure has not been modified, data recovery can be achieved by rebuilding the table.

Step 1: Create a table with the same name

In the newly created MySQL instance, you can create a table with the same name as the accidentally deleted table. The specific operations are as follows:

CREATE TABLE table1 (column1 datatype, column2 datatype, column3 datatype,....);

Step 2: Restore data

To restore deleted data, you need to first find the backup file and then execute it through the load statement Restore operation.

3. Use third-party tools to recover data

In addition, you can also use some data recovery software to perform data recovery operations. Among them, the well-known data recovery software on the market include Recuva, EASEUS Data Recovery Wizard, etc. They all have high data recovery capabilities and can help recover accidentally deleted MySQL data.

3. Prevent accidental deletion of data

In addition to using effective recovery methods, you can also pay attention to data backup and do a good job in data management to prevent accidental deletion of data. The following are several suggestions to prevent accidental deletion of data:

1. Pay attention to the security of data and do a good job of backup.

2. Turn on the safe mode of MySQL to strengthen management and prevent misoperation.

3. Use a reasonable operating authority mechanism.

4. Regularly maintain the system to ensure the health of the hardware and software.

In short, accidentally deleting data is a common problem and one of the most common technical support issues for MySQL administrators. We need to take reasonable measures to summarize and recover the lost data in a timely manner, while also ensuring Data security to avoid malicious attacks on the database.

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