Hi there, using Hibernate 5.2.16, I’m encountering an assertion error in org.hibernate.engine.internal.BatchFetchQueueHelper#removeNotFoundBatchLoadableEntityKeys assert idSet.size() == ids.length - results.size(); a) when bytecode enhancement is disabled b) in Hibernate Search with enabled byte…

I’m still struggling to create a test case for this due to lack of time, but https://hibernate.atlassian.net/browse/HHH-12835 now has solved the issue.

From the image, it looks like the results ArrayList have a duplicated User@14158 while the ids are deduplicated. Try to provide a replicating test case .

Providing a test case will be quite tricky. But I’ve just found out that this only happens when AvailableSettings.DEFAULT_BATCH_FETCH_SIZE is set. Not using batch fetches does not cause this issue.

[image] nikowitt: Providing a test case will be quite tricky. Without a test case that proves the issue, it’s not clear what exactly is not working properly and requires a fix.

Of course. I will tackle this issue ASAP.

In Hibernate 5.3.0, the error thrown is slightly different as bootstrapping fails. See https://hibernate.atlassian.net/browse/HHH-12594

The difference is now that bootstrapping fails, before the issue occured after the bootstrapping process. But anyhow, a test case exists for this one, so this can be further investigated now.

I’m going to integrate the test case and see if I can fix the issue.

Hi, i have the same problems, at least in one case I could solve it by changing an Fetch.EAGER with implicit JOIN to an Fetch.EAGER with explicit FetchMode.SELECT, which looks like an cartesian product problem to me. Problem Version: 5.2.17.Final No Problem before with 5.2.1.Final I retested Vers…

FetchType.EAGER is almost always a bad idea .

Assertion error in org.hibernate.engine.internal.BatchFetchQueueHelper

Hibernate ORM

vlad May 17, 2018, 9:11am 7

Maybe the error message has changed due to working on this issue for improving performance

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Assertion error in org.hibernate.engine.internal.BatchFetchQueueHelper

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