FetchingScrollableResultsImpl.last infinitely looping

Hibernate ORM
1

I’m upgrading code that worked in Hibernate 5 to hibernate 6, and found that one of our queries results in an infinitely looping call - locking up the SQL table.

The querystring contains a “fetch” keyword, and we use query.Scroll() to get a scrollableResults (allegedly for performance purposes?) - we then immediately call scrollableResults.last() - which never completes nor crashes.

By calling query.list() I was able to determine that the result list is empty (which is expected in this case)

I debugged the FetchingScrollableResultsImpl.last() call, and saw that it loops infinitely within these lines:

while ( !afterLast ) {
    more = next();
}

Curiously, a few lines before this there’s a check for ‘isResultSetEmpty()’ that returns true, despite the previously mentioned query.list() showing there are no results.

I’ve tried this on 6.4.0 and 6.5.0, same issue.

2

This should say “Curiously, a few lines before this there’s a check for ‘isResultSetEmpty()’ that returns false, despite the previously mentioned query.list() showing there are no results.”

3

Please try to create a reproducer with our test case template and if you are able to reproduce the issue, create a bug ticket in our issue tracker and attach that reproducer.

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