I configured Hikari following this tutorial: https://www.baeldung.com/spring-boot-hikari
When Spring Boot starts Hikari starts too, as follows in the next image:
Is it possible to configure Hikari to start when the first ReST request is being received?
Quoted from Hikari's official document on Github:
connectionTestQuery
If your driver supports JDBC4 we strongly recommend not setting this property. This is for "legacy" drivers that do not support the JDBC4
Connection.isValid() API. This is the query that will be executed just
before a connection is given to you from the pool to validate that the
connection to the database is still alive. Again, try running the pool
without this property, HikariCP will log an error if your driver is
not JDBC4 compliant to let you know. Default: none
As documentation:
"For a pooling DataSource to be created, we need to be able to verify that a valid Driver class is available, so we check for that before doing anything. In other words, if you set spring.datasource.driver-class-name=com.mysql.jdbc.Driver, then that class has to be loadable."(https://docs.spring.io/spring-boot/docs/2.1.6.RELEASE/reference/htmlsingle/)
Related
In a Spring Boot application using Log4j2, I have setup a DataSource via yaml-configuration. But since Log4j2 needs a connection pool already in the startup phase for its JDBC Appender, a second data source must be provided separately. This results in the application having two connection pools running, both writing to the same database.
My first question is:
Are there any concerns about this setup, or is this the normal approach anyway?
Alternatively, the following setup would come to mind: we programmatically initialize the DataSource, so that we have access to it. Further on, we can then programmatically extend the existing Log4j2 configuration that doesn't have a JDBC Appender yet. By doing so we can pass the pooled DataSource that we also use for the application itself.
My second question is therefore:
Are there any caveats to using the same DataSource for both the application and the Log4j2 logging framework?
Many thanks for any information that helps to clarify the situation.
I would like to know if changing the password of the DB associated with the Spring boot application affects the existing connections.
If Hikari tries to connect by reading the properties at regular intervals when managing the connection, I think there could be a connection error in this process, is that right?
Yes it does affects the connection, it will cause something like "Error establishing a database connection".
We have an application that uses several data sources. A DB underlying one of those data sources is down at the moment: IOError. Network adapter couldn't establish the connection & Socket read timed out.
Is there an annotation (or other means) of configuring Spring Boot such that it bypasses the culprit data source and still starts up: the DB is not essential in current development work. spring.datasource.continue-on-error=true doesn't seem to work. This is Spring 2.2.2.RELEASE.
using multiple datasource, so when your apps fail at start up your apps still work, i mean using memory db / sqlite to handle fail at connection error...
I'd like to add XA connection pool to my Spring based application, specifically Oracle UCP. This pool works on XADataSource and XAConnection objects. Standard DataSource.getConnection(...) methods are not supported.
Trying working with that pool (that I am able to successfully set up in Spring) I am getting an error related to the fact that getConnection(...) methods invoked by JdbcTemplate are disabled and should not be used. I am just wondering whether any of Spring JDBC classes are able to work with XADataSource and XAConnections? Probably there are another ways to use Spring with XA connection pools? Will appreciate any advices on that topic.
Just for those who may experience similar problems - Spring doesn't support directly XA connection pools (through native XADataSource.getXAConnection(...) methods). You need to write a kind of wrapper utilizing DatSource.getConnection(...) methods.
My application is using Websphere 6.1, Spring JDBC and oracle.I am using connection pooling to manage the connections.Is there any way to find out the number of connections active(alive) between the application and database at any point of time?.Can we have any indicator to let us know when a connection is/was dropped?
One option would be to manage your connection pool via JMX. Spring has excellent support for it. You just need to expose your connection pool bean via org.springframework.jmx.export.MBeanExporter. You can pick and choose the methods you want to expose. For example if you use DBCP you can use the method BasicDataSource#getNumActive().