Shutdown and Restart Statements

There are various ways to shutdown MySQL. The traditional cross platform method is to use the shutdown command in the mysqladmin client. One drawback is that it requires shell access; another is that it cannot start MySQL again automatically. There are platform specific options that can perform a restart such as using systemctl on Linux or install MySQL as a service on Microsoft Windows. What I will look at here though is the built in support for stopping and restarting MySQL using SQL statements.

MySQL 5.7 added the SHUTDOWN statement which allows you to shut down MySQL using the MySQL command-line client or MySQL Shell. The command is straight forward to use:

The SHUTDOWN command available in MySQL 5.7 and later.
The SHUTDOWN command available in MySQL 5.7 and later.

You will need the SHUTDOWN privilege to use the statement – this is the same as it required to use mysqladmin to shutdown MySQL. There is one gotcha to be aware of with the SHUTDOWN statement: it only works with the old (traditional) MySQL protocol. If you attempt to use it when connected to MySQL using the new X Protocol, you get the error: ERROR: 3130: Command not supported by pluggable protocols as shown in the next example:

Executing SHUTDOWN when connected through the X Protocol causes error 3130.
Executing SHUTDOWN when connected through the X Protocol causes error 3130.

The RESTART statement, on the other hand, works through both protocols and also requires the SHUTDOWN privilege:

The RESTART command available in MySQL 8.0.
The RESTART command available in MySQL 8.0.

For the restart to work, it is necessary that MySQL has been started in presence of a “monitoring service”. This is the default on Microsoft Windows (to disable the monitoring service start MySQL with --no-monitor). On Linux the monitoring service can for example be systemd or mysqld_safe.

As an example of where the RESTART statement comes in handy is for MySQL Shell's AdminAPI for administrating a MySQL InnoDB Cluster cluster. MySQL Shell can when connected to MySQL Server 8.0 use the new SET PERSIST syntax to make the required configuration changes and then use the RESTART statement to restart the instance to make non-dynamic configuration changes take effect.

The SHUTDOWN and RESTART statements may not be the most important changes in MySQL 5.7 and 8.0, but they can be handy to know of in some cases.

I have worked with MySQL databases since 2006 both as an SQL developer, a database administrator, and for more than eight years as part of the Oracle MySQL Support team. I have spoken at MySQL Connect and Oracle OpenWorld on several occasions, and addition to his books, I regularly blog on MySQL topics and has authored around 800 documents in the Oracle Knowledge Base. I have contributed to the sys schema and four Oracle Certified Professional (OCP) exams for MySQL 5.6 to 8.0. I earned a PhD in computational chemistry before changing to work with MySQL and other software development in 2006. I live in Sydney, Australia, and enjoys spending time outdoors walking, traveling, and reading. My areas of expertise include MySQL Cluster, MySQL Enterprise Backup, performance tuning, and the Performance and sys schemas.

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