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Multi tenant audit logging in java with spring framework?

We have a multi-tenant Spring Web app setup with Hibernate as JPA. We use a tenant per schema. We like to use tools like Envers or JaVers for Audit logging such that every db schema has its own audit tables.
How have you implemented this? Or would you implement it?
I have changed the code of JaVers a bit such that when it retrieves the db schema I will return the db schema that belongs to the logged-in user. This works partly as some tables are contained in the shared public schema, however, currently at the place were JaVers retrieves the db schema I don't have this entity/table info. I am thinking about changing JaVers code further such that I have this entity/table info, but isn't there a better library/approach to support multi-tenant?
Sorry for not posting any code 🙈

How to map different queries for different database in one project in springboot?

In my current project, I am doing migration from Oracle to Azure SQL Server. Right now, we need to integrate both database working with same queries. Depending on what I have on my configuration, project will connect with Oracle or Azure SQL.
Problem is, there are some queries that are not compatible for both database types. For instance, nextval works for Oracle, but not with Azure SQL:
In Oracle:
... values(unique_id_seq.nextval ...
In Azure SQL:
... values(NEXT VALUE FOR unique_id_seq, ...
Therefore, I think I will need to create two different queries and my project should know which database I am loading and it should map to correct query. Is this possible to achieve in springboot? I am pretty new to springboot..
(One of my co-worker said If possible try to convert query into HQL or add the mapping entity, instead of creating separate queries., but I am not sure what this means.)

Try using Spring Boot with Hibernate.

Is it possible to make Spring Boot JPA Hibernate application to automatically create tables with necessary columns and relations from JPA entities?

I am a newbie that only knows basics of Java Core. I have test task where I need to create simple REST Web Service with Spring Boot.
I wrote all the logic in Java Core, and now I try to wrap it in all these technologies.
I am using this guide:
https://spring.io/guides/tutorials/rest/
Here they have JPA entities and #Table annotation, where table name is specified, but there are no SQL scripts to create tables in this guide.
So I thought JPA will create database and tables for entities by itself, but when I uncomment #Table annotation it says "Cannot resolve table '<table_name>'"
I am using IntelliJ IDEA with Spring Boot Maven project with imported Spring Web, H2 and JPA (like the guide tells to do).
I also configured H2 Data Source and tested the connection: works fine. There is a schema, but no tables.
Here is my application.properties:
spring.h2.console.enabled=true
spring.h2.console.path=/h2_console
spring.datasource.url=jdbc:h2:~/kaylemains
spring.datasource.platform=h2
spring.datasource.initialization-mode=always
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.driverClassName=org.h2.Driver
spring.jpa.generate-ddl=true
spring.jpa.database-platform=org.hibernate.dialect.H2Dialect
spring.jpa.hibernate.ddl-auto = update
spring.jpa.show-sql=true
logging.level.org.hibernate.SQL=DEBUG
logging.level.org.hibernate.type.descriptor.sql.BasicBinder=TRACE
As in the guide, I add entities in LoadDatabase class like this:
#Bean
CommandLineRunner initTournaments(TournamentRepository repository) {
return args -> {
log.info("Preloading " + repository.save(new Tournament("Kayle Mains Competition: Summoner's Gorge", 16)));
};
}
So my question is: can I have file-stored H2 database and do everything with the it (including table creation) from my Java code?
OR it is necessary to create tables manually (by writing SQL scripts with CREATE TABLE) and construct them so that all entities work fine? (that means defining foreign key columns etc.), and only after that will JPA be able to work with this database? Do I need to add #Column annotation to every field, and JPA won't do it by itself for its Entities?
Why am I getting this error of "Cannot resolve table"? Of course it cannot be resolved because it does not exist yet, I thought JPA & Hibernate will create it for me based on entity classes...

Here in Baeldung you have all the information about the properties to ddl generation
Spring provides a JPA-specific property which Hibernate uses for DDL generation: spring.jpa.hibernate.ddl-auto.
create – Hibernate first drops existing tables, then creates new tables
update – the object model created based on the mappings (annotations or XML) >is compared with the existing schema, and then Hibernate updates the schema >according to the diff. It never deletes the existing tables or columns even if >they are no more required by the application
create-drop – similar to create, with the addition that Hibernate will drop >the database after all operations are completed. Typically used for unit testing
validate – Hibernate only validates whether the tables and columns exist, otherwise it throws an exception
none – this value effectively turns off the DDL generation
We have to set the value carefully or use one of the other mechanisms
to initialize the database.
If the problem is still present go to Settings -> Inspections, and uncheck the option "Unresolved database references in annotation"

How do I enable Hibernate auto ddl table creation?

I recently switched from Ebean to Hibernate and I want to enable Hibernate table auto-geration.
When I used Ebean, it was quite simple, I just activated the evolutions and Ebean created all my database schemas.
How I can do that with Hibernate?

You can use hibernate.hbm2ddl.auto which can Automatically validates or exports schema DDL to the database when the SessionFactory is created. With create-drop, the database schema will be dropped when the SessionFactory is closed explicitly.
e.g. validate | update | create | create-drop
So the list of possible options are,
validate: validate the schema, makes no changes to the database.
update: update the schema.create: creates the schema, destroying previous data.
create-drop: drop the schema at the end of the session.

Dynamic schema selection for Spring Data JPA repositories with schema coming from database

as the title says, I have an application (Spring Boot) which must execute some queries on specified objects on a SQL Server database. Such database having a single catalog and multiple schemas, which must be selected based on a previous query and some command line parameters.
I cannot seem to implement a strategy which involves Hibernate multi-tenancy, as most of the tutorials and answers on this site deal with schema names coming from a web request or an external parameter, while I need a database connection before creating the main multi-tenant EntityManager. So, I switched to a custom DataSource which tries to change the connection's default schema (using ALTER USER... WITH DEFAULT_SCHEMA = ...). But this also fails because the logged-in user does not have permission to alter his own default schema.
So I'm at a loss of what to do. Any suggestions?

Just create an EntityManager(Factory) per schema and put them in a map to choose from.
If you don't know the schemas before hand you can create EntityManager(Factory)s as soon as you learn about a schema.
that you can configure an EntityManagerFactory programatically.