How can I prevent @Transactional from holding onto connections from the data source that is not involved in the transaction?

Question

I have 2 datasources in my SpringBoot app.

In one class without any annotation there is a method annotated with @Transactional which uses the second datasource, buy always gets a ConnectionHolder from primary dataset and holds its connection which is never used in this class.

.s.t.s.TransactionSynchronizationManager :  Retrieved value [org.springframework.orm.jpa.EntityManagerHolder@6f9d4ae7] for key [org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean@4c9bed65] bound to thread [http-nio-8080-exec-1]

.s.t.s.TransactionSynchronizationManager :  Bound value [org.springframework.jdbc.datasource.ConnectionHolder@55cec771] for key [HikariDataSource (HikariPool-sqlServer)] to thread [http-nio-8080-exec-1]

.s.t.s.TransactionSynchronizationManager :  Initializing transaction synchronization

Answer 1

Can you try setting transaction manager for the Transactional annotation you are using.

https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/transaction/annotation/Transactional.html#transactionManager--

This can help you to specify that use this transaction manager with this ds for this class.

Hope it helps.