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Spring Hibernate transaction - read only vs read write

I am facing a weird problem with Spring Boot(2.3.7) + PostgreSQL v12 (row level security) + Hibernate (5.x).
Here are the steps that I am executing
A procedure accepts an input variable and creates temporary table. The variable is then inserted in temporary table.
Spring Advice which executes for all #Service annotation and invokes a procedure with a variable (call it custom_id).
#Transactional attribute is specified on all #Service classes.
PostgreSQL row level security has been enabled on the tables being queried and updated.
Row level security applies filter based on the variable stored (custom_id value) in temporary table.
All update, select, insert operations are executed using custom implementation of JpaRepository (interface based)
This works fine as long as there are only select operation performed on the database. But starts to fail with code having a combination of select and updates. The code simply fails with a message as it is not able to locate the temporary table.
I enabled trace for Spring transaction and found that there are few statements like
No need to create transaction for XXX
While code that performs update operation has statements like
Getting transaction for XXX
After searching for a while, I realised that SimpleJpaRepository has #Transaction with readonly flag set to true. This results in SELECT operation getting executing in transaction less mode.
Procedure
create or replace procedure proc_context(dummy_id uuid) AS $context_var$
declare
begin
create temp table if not exists context_metadata
(
dummy_id uuid
)
on commit drop;
insert into context_metadata values(dummy_id);
end;
$context_var$ LANGUAGE plpgsql;
ERROR
Following error is logged in console
ERROR: relation "context_metadata" does not exist
What I tried
Tried implementing custom transaction manager and explicitly invoking the procedure to set the temporary variable value (Didn't work). Refer below
protected void prepareSynchronization(DefaultTransactionStatus status, TransactionDefinition definition) {
super.prepareSynchronization(status, definition);
if (status.isNewTransaction() || status.isReadOnly() || status.isNewSynchronization()) {
UUID someID = ....;
Query query = entityManager.createNativeQuery("CALL proc_context(?);");
query.setParameter(1, someID);
query.executeUpdate();
}
}
Tried setting #Transactional notation with readonly set to false on all repositories.
What I am looking for?
Unfortunately due to this behaviour, the row-level security implementation is not working in my code. Is there any way to disable read-only transactions using a global property OR provide me with any hint to overcome this problem?

Finally, I could figure out after 2 days of battle. The problem was multi-faceted.
I noticed hibernate.transaction.flush_before_completion property set to true in application.properties file. I had to remove that property.
Developer had written a very messy code to update the entity attributes (Was performing select, then creating new instance, populating attributes and then calling save method). All this ruckus to update one single attribute.
Tested the code and everything worked fine.

spring.datasource.url how to create multiple enum/domain before hibernate is scanning the entities

I have spring boot application with pgsql as db. I am writing test cases for the api's and for the test cases i am using h2 db. I have multiple entities where i have multiple enums. For the test cases we have
spring.jpa.hibernate.ddl-auto = create-drop
When hibernate is creating the tables from entity it is giving Unknown data type: "enum_type1".
I took a reference from this question:
How to fake ENUM columns in the H2 database for play unit testing?
So i updated my property as follows:
spring.datasource.url= jdbc:h2:mem:test;MODE=PostgreSQL;INIT=CREATE DOMAIN IF NOT EXISTS enum_type1 as VARCHAR(255),CREATE DOMAIN IF NOT EXISTS enum_type2 as VARCHAR(255);DB_CLOSE_ON_EXIT=FALSE
But it is giving following error:
org.h2.jdbc.JdbcSQLSyntaxErrorException: Syntax error in SQL statement "CREATE DOMAIN IF NOT EXISTS enum_type1 AS VARCHAR(255),[*]CREATE DOMAIN IF NOT EXISTS enum_type2 AS VARCHAR(255)"; SQL statement:
So how can we create multiple enum/domain before hibernate is scanning the entities?
Any help will be appreciated, Thanks.

You can't use a comma as a separator between statements. If you want to specify multiple statements in INIT parameter, they should be separated with \;. Note that INIT=something parameter should be separated from other parameters, such as DB_CLOSE_ON_EXIT with ; (without the \).
jdbc:h2:mem:test;MODE=PostgreSQL;INIT=CREATE DOMAIN IF NOT EXISTS enum_type1 as VARCHAR(255)\;CREATE DOMAIN IF NOT EXISTS enum_type2 as VARCHAR(255);DB_CLOSE_ON_EXIT=FALSE
H2 also has a built-in ENUM data type, it should be better to use it instead of VARCHAR.
PostgreSQL compatibility mode should be normally used with DATABASE_TO_LOWER=TRUE.
And the whole idea to use different DBMS for tests and production doesn't look good. Normally you should use multiple DBMS only when your application is initially designed to work with them all.

How to get bound parameters out of a Hibernate Criteria object?

I am running a complex query via the Hibernate Criteria API. During debug, I would like to be able to extract and log the parameters that have been bound to the criteria object. Using Hibernate's org.Hibernate.type logger is not an option because during the server start there are many many queries that are run and the logger causes a serious performance hit, and as we are using Hibernate 3.5, it cannot be configured to be turned on before and after the specific method call, only when the server starts.
As far as getting the SQL query itself, in this answer someone posted excellent code that allows for extracting the SQL from a criteria, is there a similar solution for the bound parameters?

You can log the Criteria and the Restrictions will be displayed as well:
Criteria criteria = session.createCriteria(Post.class)
.add(Restrictions.eq("title", "post"));
LOGGER.info("Criteria: {}", criteria);
will display:
Criteria: CriteriaImpl(com.vladmihalcea.book.hpjp.hibernate.association.AllAssociationTest$Post:this[][title=post])

spring jdbc template returns an empty result

I have the following code
resultList = daoResources.jdbcTemplate.query(sql, selectParams, new BeanPropertyRowMapper(resultClass));
SQL when run with the selectParams against database, I get result. The selecting fields name of the sql matches with the fields in the resultClass too. But for above code, I get an empty resultList.
Where could be the problem?

Debugging is your friend in this scenario. I suggest you enable debug logs for jdbc template to see what sql's and bind parameters are sent to database. Below is from the 3.0.x reference doc
All SQL issued by this class is logged at the DEBUG level under the
category corresponding to the fully qualified class name of the
template instance (typically JdbcTemplate, but it may be different if
you are using a custom subclass of the JdbcTemplate class).

How to support support SqlServer's ".." in HyperSQL?

tl;dr: I am trying to unit test some SqlServer queries which state the db name but they do not seem to work in HyperSql.
We are using Sql Server in production and I am trying to use HyperSQL as my database for unit testing. I am trying to test a class that creates SQL queries so stubbing out the database is not an option as having the queries parsed by a real database is part of the test.
Queries are supposed to be created in the form of SELECT * FROM EntAsdfDb007..Data_Table, although we can use the schema name ( 'db' ) if we wish.
From what I understand about the SELECT format for SqlServer, it allows you to specify the name of database followed by the name of schema. Also, you can drop the name of the database and have it inferred.
In HyperSqlDb I have been able to create the schema 'db' and create the necessary tables within it, and have been able to create tables within that schema but I have not be able to query with the database name even after setting the DB name using .setDatabaseName(). The exception I get is:
Caused by: org.hsqldb.HsqlException: user lacks privilege or object not found: ENTASDFDB007
Just to be clear: I am unit-testing a class that uses SQL like SELECT * FROM EntAsdfDb007..Data_Table. I am trying to set up an instance of HyperSql for unit testing purposes but HyperSql seems to reject the syntax used.

That won't be possible.
HyperSQL cannot be changed to accept non-standard naming schemes.

It is possible. HSQLDB does have one catalog per database. The catalog name is PUBLIC by default, which you can change.
ALTER CATALOG PUBLIC RENAME TO EntAsdfDb007
You can then access your table with
SELECT * FROM EntAsdfDb007.db.Data_Table