MySQL event listener#

Примечание

Ниже приведена оригинальная документация Trino. Скоро мы ее переведем на русский язык и дополним полезными примерами.

The MySQL event listener plugin allows streaming of query events to an external MySQL database. The query history in the database can then be accessed directly in MySQL or via Trino in a catalog using the MySQL connector.

Rationale#

This event listener is a first step to store the query history of your Trino cluster. The query events can provide CPU and memory usage metrics, what data is being accessed with resolution down to specific columns, and metadata about the query processing.

Running the capture system separate from Trino reduces the performance impact and avoids downtime for non-client-facing changes.

Requirements#

You need to perform the following steps:

  • Create a MySQL database.

  • Determine the JDBC connection URL for the database.

  • Ensure network access from the Trino coordinator to MySQL is available. Port 3306 is the default port.

Configuration#

To configure the MySQL event listener plugin, create an event listener properties file in etc named mysql-event-listener.properties with the following contents as an example:

event-listener.name=mysql
mysql-event-listener.db.url=jdbc:mysql://example.net:3306

The mysql-event-listener.db.url defines the connection to a MySQL database available at the domain example.net on port 3306. You can pass further parameters to the MySQL JDBC driver. The supported parameters for the URL are documented in the MySQL Developer Guide.

And set event-listener.config-files to etc/mysql-event-listener.properties in Config properties:

event-listener.config-files=etc/mysql-event-listener.properties

If another event listener is already configured, add the new value etc/mysql-event-listener.properties with a separating comma.

After this configuration and successful start of the Trino cluster, the table trino_queries is created in the MySQL database. From then on, any query processing event is captured by the event listener and a new row is inserted into the table. The table includes many columns, such as query identifier, query string, user, catalog, and others with information about the query processing.

Configuration properties#

Property name

Description

mysql-event-listener.db.url

JDBC connection URL to the database including credentials