Is there a way to configure the H2 Compatibility Mode for the H2 Database that Spring Boot can auto configure to replace your regular database without just replacing it?
There are documented ways of disabling the autoconfiguration test database replacement:
https://stackoverflow.com/a/43557541/141042
I don't mind doing something like this, but most of the alternatives come with other complexities:
if you add a application.properties in your test classpath, this replaces your main application.properties during test runs, so then you're stuck maintaining two files (e.g. https://github.com/spring-projects/spring-boot/issues/10271)
if you set up a profile for test runs, then you have to make sure that any test needing the test database is marked with the profile
Is there a better way of doing this? I like the simplicity of the Spring Boot auto configured test database, but it seems like I have to force it into MySQL compatibility mode now to continue to work with my existing migrations.
So is there:
a way to configure the compatibility mode of h2 when spring autoconfigures the test database without disabling that mechanism?
a way of specifying the jdbc url for all tests without having to modify each test (e.g. to include a profile) or maintaining two application property files (e.g. a new application.properties in src/test/resources)
There isn't an option to set a custom URL for the embedded datasource that Spring Boot replaces in your tests. We offer a way to specify which connection type you want but that doesn't include the URL itself. I have no idea how easy we could add that but it's worth looking at least, I've created issue #19038
As for specifying the URL, you shouldn't add an application.properties in your test classpath for the reason you've mentioned. The SO thread you've referenced already has an answer that refers to application-test.properties.
How to check through spring-boot that if the database schema is already present do not run but run if no matching schema. Can I do the following through spring-boot flyway integration.
DEV - already has the database tables matching the sql scripts (e.g V1_Baseline.sql has both table creation and reference data) so should not run this but will need to create the internal SCHEMA_VERSION table and make this script as already run so that V2_....sql will run next)
TEST - has tables that should not be dropped but the scripts need to be run and internal SCHEMA_VERSION table created.
PROD - this is empty. So no issues should be there (same as test i guess).
From flyway site I saw this:
flyway clean (cannot run - nothing should be dropped)
flyway baseline (i think this is the one I need? check if current db is matching then just make current scripts as baseline and dont run if not run the scripts)
Nothing concrete here on here spring io too and on baeldung too.
I think answer is here with baseline and doing some checks but not sure what works.
Baseline is indeed what you need here as it serves this exact purpose.
Is there a 'community/Spring' approved method with Boot to have different datasource target for the same project?
Should I include both connector (H2 and Mysql) in the project dependencies and just change the jdbc url in my application.yml?
We are switching our tomcat instance to a Boot project, old habits of having jdbc jar as provided. I was wondering if this was still supported or desired in a boot fat jar/war exec.
If I understood Your question correctly, there are two scenarios, that You could be intrested in.
First is where You use both datasources at once in your project (ex. getting data from both H2 and MySQL in the same time, or one after another).
Second scenario is when You use two datasources but not at once, for example: H2 for test/debug project build, MySQL for production. Another sub-scenario is like You want something like primary/secondary datasources.
Solution for first scenario is to add two dependencies, disable Boot autoconfiguration (autoconfiguration won't work for multiple datasources) for databases and manually configure tho separate EntityManagers etc. (more info here: https://docs.spring.io/spring-boot/docs/current/reference/html/howto-data-access.html#howto-use-two-entity-managers)
Sorry that I can't provide any code sample but I can't access my work repo from home.
Moving to the second scenario what You can do is, use profiles.
You have to create separate profile and application-something.yml file for that profile. Inside you configure your second datasource, and then in dependencies you can make your second database dependency to add only with specific profile as well - but here im not 100% sure, I don't remember how we did it in work ;d.
And again, I cant paste any example but here is some help:
Profiles,
Profile-specific configuration files
An then there is a sub-scenario that I mentioned earlier. Marking datasource as #Primary But here I've never used it, I just know it exists: Link
Edit2: After some rethinking, I think this is the way to go with Boot and active profiles: Spring Boot Maven Plugin
Sorry for a lot of spam, and reconsiderations. That was quite confusing for sure.
Hope that helps,
I am building a stand alone java application using Spring JPA frame
work. I am able to access the DB in below scenario: if I give the
DB details in application.properties file as
spring.datasource.url=******** spring.datasource.username=******
spring.datasource.password=******
then it's working properly.
but I have to create two DB connections in the same application so,
I changes the names as below
spring.Datasource1.url=********* spring.Datasource1.username=******
spring.Datasource1.password
spring.Datasource2.url=************ spring.Datasource2.username=****
spring.Datasource2.password=*****
then it's not working.
Can you please provide the solution for it?
I have uploaded my code base in below location.
https://github.com/nagtej/MultipleDataSource
This might be helpful to you http://docs.spring.io/spring-boot/docs/current/reference/htmlsingle/#howto-two-datasources
Also, to connect to multiple data sources you would need to manually configure a DataSource, EntityManagerFactory and JpaTransactionManager.
For this, you can have a look at code placed at https://github.com/spring-projects/spring-data-examples/tree/master/jpa/multiple-datasources
Another good example for this is shared at http://xantorohara.blogspot.com.au/2013/11/spring-boot-jdbc-with-multiple.html
I use JDBC and created h2 database called usaDB from sql script. Then I filled all tables with jdbc.
The problem is that after I connect to usaDB at localhost:8082 I cannot see on the left tree
my tables. There is only INFORMATION_SCHEMA database and rootUser which I specified creating usaDB.
How to view the content of tables in my h2 database?
I tried query SELECT * FROM INFORMATION_SCHEMA.TABLES.
But it returned many table names except those I created. My snapshot:
I had the same issue and the answer seems to be really stupid: when you type your database name you shouldn't add ".h2.db" suffix, for example, if you have db file "D:\somebase.h2.db" your connection string should be like "jdbc:h2:file:/D:/somebase". In other way jdbc creates new empty database file named "somebase.h2.db.h2.db" and you see what you see: only system tables.
You can use the SHOW command:
Using this command, you can lists the schemas, tables, or the columns of a table. e.g.:
SHOW TABLES
This problem drove me around the twist and besides this page I read many (many!) others until I solved it.
My Use Case was to see how a SpringBatch project created in STS using :: Spring Boot :: (v1.3.1.RELEASE) was going to behave with the H2 database; to do the latter, I needed to be able to get the H2 console running as well to query the DB results of the batch run.
This is what I did and found out:
Created an Web project in STS using Spring Boot:
Added the following to the pom.xml of the latter:
Added a Spring configuration file as follows to the project:
This solves the Web project deficiencies in STS. If you run the project now, you can access the H2 console as follows: http://localhost:8080/console
Now create a SpringBatch project in STS as follows (the alternative method creates a different template missing most of the classes for persisting data. This method creates 2 projects: one Complete, and the other an initial. Use the Complete in the following.):
The SpringBatch project created with STS uses an in memory H2 database that it CLOSES once the application run ends; once you run it, you can see this in the logging output.
So what we need is to create a new DataSource that overrides the default that ships with the project (if you are interested, just have a look at the log messages and you will see that it uses a default datasource...this is created from:
o.s.j.d.e.EmbeddedDatabaseFactory with the following parameters:
Starting embedded database: url='jdbc:hsqldb:mem:testdb', username='sa')
So, it starts an in memory, and then closes it. You have no chance of seeing the data with the H2 console; it has come and gone.
So, create a DataSource as follows:
You can of course use a properties file to map the parameters, and profiles for different DataSource instances...but I digress.
Now, make sure you set the bit that the red arrow in the picture is pointing to, to a location on your computer where a file can be persisted.
Running the SpringBatch (Complete project) you should now have a db file in that location after it runs (persisting Person data)
Run the Web project you configured previously in these steps, and you WILL :=) see your data, and all the Batch job and step run data (et voila!):
Painful but rewarding. Hope it helps you to really BOOTSTRAP :=)
I have met exactly this problem.
From what you describe, I suppose that you connect your jdbc with the "real" h2 server, but you are connecting on web application to database by the wrong mode (embedded-in-memory mode, aka h2mem). It means that h2 will create a new database in-memory, instead of using your true database stored elsewhere.
Please make sure that when you connect to this database, you use the mode Generic H2 (Server), NOTGeneric H2 (Embedded). You can refer to the picture below.
Version of jar file and installed h2 database should be same.
If in case you have created and populated H2 database table using maven dependency in spring boot, then please do change the JDBC URL as jdbc:h2:mem:testdb while connecting to H2 using web console.
It is an old question, but I came across the same problem. Eventually I found out that the default JDBC URL is pointing a test server rather than my application. After correcting it, I could access the right DB.
I tried with both Generic H2 (Embedded) and the Generic H2 (Server) options, both worked as long as the JDBC URL: is provided correctly.
In grails 4.0.1 the jdbc URL for development is jdbc:h2:mem:devDb. Check your application.yml file for the exact URL.
For the people who are using H2 in embedded(persistent mode) and want to "connect" to it from IntelliJ(other IDEs probably apply too).
Using for example jdbc url as follows: jdbc:h2:./database.h2
Note, that H2 does not allow implicit relative paths, and requires adding explicit ./
Relative paths are relative to current workdir
When you run your application, your workdir is most likely set to your project's root dir
On the other hand, IDE's workdir is most likely not your project's root
Hence, in IDE when "connecting" to your database you need to use absolute path like: jdbc:h2:/Users/me/projects/MyAwesomeProject/database.h2
For some reason IntelliJ by default also adds ;MV_STORE=false. It disables MVStore engine which in fact is currently used by default in H2.
So make sure that both your application and your IDE use the same store engine, as MVStore and PageStore have different file layouts.
Note that you cannot "connect" to your database if your application is using it because of locking. The other way around applies too.
In my case the issue was caused by the fact that I didn't set the h2 username, password in java. Unfortunatelly, Spring didn't display any errors to me, so it was not easy to figure out. Adding this lines to dataSource method helped me fix the issue:
dataSource.setUsername("sa");
dataSource.setPassword("");
Also, I should have specified the schema when creating tables in schema.sql
Selecting Generic H2 (Server) solved for me. We tempted to use default Generic H2 (Embedded) which is wrong.