MySQL: How to Backup (Dump) and Restore Database Using mysqldump

This article shows the proper way how to dump and restore MySQL database from command line in Linux using mysqldump and mysql commands.

If you are using MySQL or MariaDB Databases it is very important for you to understand how to take backup and restore data. In addition, you need to keep regular backups of the database and this will help you to restore your data if your application crashes or the data is corrupted by any system failure.

MySQL and MariaDB include command-line tools that you can use to quickly and easily dump and restore databases. The mysqldump tool is used to export the contents of a database to a text file, while the mysql client can be used to import data from a text file into a MySQL/MariaDB database.

How to Use the MySQL Dump Command

The mysqldump command line utility exports databases to SQL text files. In other words, it is used for taking the MySQL database dump.

The syntax for mysqldump command is given below:

mysqldump -u [username] -p [database_name] > [filename].sql

Where:

• username is your MySQL/MariaDB username.
• -p prompt for password for this user.
• database_name is the name of the database you want to backup.
• filename.sql is the full path to the sql dump file that will contain the backup.

Database procedures, functions, views and events are dumped at the time of backup.

mysqldump: Backup a Single MySQL Database

In this example, the database is named my_wordpress. Replace this with the name of the database you wish to export. According to the syntax, the backup file will be created at the current location.

mysqldump -u root -p my_wordpress > my_wordpress_backup.sql

After the command is run, enter your MySQL root password.

This creates a MySQL dump file named my_wordpress_backup.sql that contains all of the SQL statements to create tables and restore data into an existing database. If any errors occur during the export process, mysqldump will print them to the screen.

The command will produce no visual output, but you can inspect the contents of my_wordpress_backup.sql using head command to check if it’s a legitimate MySQL dump file.

head -n 5 my_wordpress_backup.sql

-- MariaDB dump 10.19  Distrib 10.5.9-MariaDB, for Linux (x86_64)
-- Host: localhost    Database: my_wordpress
 
-- Server version    10.3.27-MariaDB-0+deb10u1

mysqldump: Backup Multiple MySQL Databases

To backup multiple MySQL databases with one command you need to use the --databases option followed by the list of databases you want to backup. In addition, you can put the result file in a location of your choice.

Run the following command to create a MySQL dump file my_backup.sql in /home/backups directory of two databases named my_wordpress and ftpusers.

mysqldump -u root -p --databases my_wordpress ftpusers > /home/backups/my_backup.sql 

mysqldump: Backup All MySQL Databases

Use the --all-databases option to back up all the MySQL databases:

mysqldump -u root -p --all-databases > all_db_backup.sql

How to Create a Compressed MySQL Database Backup

If the database size is very large it is a good idea to compress the output. To do that simply pipe the output to the gzip command, and redirect it to a file as shown below:

mysqldump -u root -p my_wordpress | gzip > my_wordpress_backup.sql.gz

mysql: Restore MySQL from a MySQL Dump File

To restore a backup created with mysqldump, you will need to use the mysql command.

mysql -u [username] -p [database_name] < [filename].sql

Where

• username is your MySQL/MariaDB username.
• -p prompt for password for this user.
• database_name is the name of the database in which you want to restore.
• filename.sql is the full path to the sql dump file that contain the backup.

mysql: Restore Single MySQL Database

You can restore all tables from the MySQL dump file of any particular database.

The restore is simply performed with the below command, where we are again specifying a user and to be prompted for a password, and passing the my_wordpress_backup.sql file into the database my_wordpress.

mysql -u root -p my_wordpress < my_wordpress_backup.sql

You will be prompted for the password of your MySQL user.

Once this completes the database should be available in the running instance of MySQL. The MySQL dump file that you imported from will also still exist, so you can either store that securely at this point or delete it if it is no longer required.

mysql: Restore All MySQL Databases

You can restore all databases of any MySQL server to another MySQL server from MySQL dump file.

mysql -u root -p < all_db_backup.sql

Conclusion

Now you can keep regular backup of your database files and restore the data when require by following above steps.

This tutorial also applies when you wish to migrate to a new server. Simply back up the database on your old server, and upload the MySQL dump file to the new server. Create a destination database on the new server, then execute the uploaded MySQL dump file in the new database. In addition to, you should also recreate users and permissions from the old MySQL server to the new one.

For more detailed information, here’s the link to the official documentation.

If you have any questions or feedback, feel free to leave a comment.