Hibernate 6, id generator table strategy start value issue

Hibernate ORM
1

Tried the following test case in hibernate 6.2.2:
Created entity with the following setup for id

@GeneratedValue(generator= "entityD", strategy = GenerationType.TABLE)
    @TableGenerator(name = "entityD", table="my_seq",pkColumnName = "my_seq_name", valueColumnName = "my_seq_val")

after that update generator for corresponding entity to 50 in the my_seq table via sql.
and ask hibernate to insert new entity.
The id will be assigned is 2, while I would expect 51…(or 52, or >50 I don’t care)
if I update generator to 100, the assigned id will be 52…

Seems a bug? In prev versions(3-5) it was working as expected.

Looking briefly in the code I see hibernate reads value from the table, updates with increment and then returns the value that was read, and after that applies formula value read - (increment size-1).
Seems logic should either return value after update or don’t substract increment size, which is 50 by default…

Test that demonstrates issue

2

https://hibernate.atlassian.net/browse/HHH-16634

3

See the migration guide about what to do here: hibernate-orm/migration-guide.adoc at 6.0 · hibernate/hibernate-orm · GitHub
You have to update the sequence to a multiple of allocationSize + 1, as that is what Hibernate does internally.

4

@beikov, I couldn’t find any explicit references of the HiLo algorithm int the migration guide.

Does the new implementation accounts for the HiLo algorithm use cases??

5

HiLo is the default optimizer. The change that happened in ORM 6 is that now a sequence per entity is created/expected by default instead of a global sequence. You should be able to revert to the old behavior if you want by setting hibernate.id.db_structure_naming_strategy=legacy

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