Connection used in the event.
EntityManager used in the event transaction. All database operations in the subscribed event listener should be performed using this entity manager instance.
可选parametersParameters used in the query.
Query that is being executed.
QueryRunner used in the event transaction. All database operations in the subscribed event listener should be performed using this query runner instance.
BeforeQueryEvent is an object that broadcaster sends to the entity subscriber before query is ran against the database.