[hibernate-dev] Negative sequence numbers

I see a comment on HHH-10219 that sounds like negative sequence values are supported by NoopOptimizer [1], but it does not seem to work. I've pushed a test case to my fork [2] with an entity defined as: @Entity( name = "TheEntity" ) @Table( name = "TheEntity" ) public static class TheEntity { @Id @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "ID_GENERATOR") @SequenceGenerator(name = "ID_GENERATOR", sequenceName = "ENTITY_SEQ", initialValue= -10, allocationSize = -1) public Integer id; } The first generated value is -10; the second generated value should be -11, but it is -9. The sequence is exported as: create sequence ENTITY_SEQ start with -10 increment by 1 In the debugger, I can see that NoopOptimizer is being used, which has the correct incrementSize (-1). The problem is that SequenceStructure#getSourceIncrementSize always returns 1. This is because SequenceStructure#applyIncrementSizeToSourceValues gets initialized to false because NoopOptimizer#applyIncrementSizeToSourceValues returns false. [3] If I change NoopOptimizer#applyIncrementSizeToSourceValues to return true, then the test passes. Unfortunately, SequenceHiLoGeneratorNoIncrementTest fails though because Hibernate tries to create a sequence that increments by 0. If I define NoopOptimizer#applyIncrementSizeToSourceValues as follows, both my test [2] and SequenceHiLoGeneratorNoIncrementTest pass. public boolean applyIncrementSizeToSourceValues() { return getIncrementSize() != 0; } Should Hibernate support negative sequence values? If so, is my proposed fix OK? Regards, Gail [1] https://hibernate.atlassian.net/browse/HHH-10219?focusedCommentId=73362&a... [2] https://github.com/gbadner/hibernate-core/tree/negative-sequence-values [3] https://github.com/hibernate/hibernate-orm/blob/master/hibernate-core/src...