jdbcFetchSize seems to be ignored

Hibernate ORM
1

Hi there,

We have upgraded some of our apps to Spring Boot 3, which also brings Hibernate 6. Since the upgrade we have noticed that the hibernate.jdbc.fetch_size property is not being respected. After some debugging I can see that the jdbcFetchSize field in SessionFactoryOptionsBuilder is being set properly but it looks like it’s not being read. Compared it with Hibernate 5 and I can see it being read as expected. Before creating a ticket for this I thought I would check it here, maybe someone has a solution.

There is a Spring issue that was closed: spring.jpa.properties.hibernate.jdbc.fetch_size not working Spring 3.X and Oracle · Issue #2835 · spring-projects/spring-data-jpa · GitHub
and a Stack Overflow post as well: java - spring.jpa.properties.hibernate.jdbc.fetch_size not working for Spring Framework 6.x and Oracle? - Stack Overflow

Thanks,
Balazs

2

From looking at the code, I can see that the JDBC fetch size is applied in org.hibernate.engine.jdbc.internal.StatementPreparerImpl#setStatementFetchSize. You can debug that to understand what is happening in your case.

3

I tried that but it never gets called. What I can see is that when running the query with Hibernate 6 it uses a StatementPreparationTemplate whereas on H5 it uses a QueryStatementPreparationTemplate.

4

this is stack on H6

image
image893×775 59.7 KB

5

and this is on H5:

image
image940×974 156 KB

6

Looks like a bug. Please create an issue in the issue tracker(https://hibernate.atlassian.net) with a test case(hibernate-test-case-templates/JPAUnitTestCase.java at main · hibernate/hibernate-test-case-templates · GitHub) that reproduces the issue.

7

@beikov @balazs
Wanted to check if there is a bug created for this.

8

https://hibernate.atlassian.net/browse/HHH-16872

Following Bug has been created to track this.