Table alias names of subtype tables in native query with joined inheritance

Hibernate ORM
1

Hi, I’m having an entity, let’s call it Item, using @Inheritance(strategy = InheritanceType.JOINED) that has 6 subtypes. Now I’m using a native query like this:

SELECT {i.*}
FROM items i
LEFT OUTER JOIN subtype1 i_1_ ON i.id = i_1_.id
...

with a JOIN per subtype. For the subtype column selects, {i.*} will be resolved into selects with the format i_*_, where the * is a number that seems to be rather randomly assigned. E.g. in the full query I need to use the numbers 1,2,3,6,7,8 as aliases for the subtype joins as this seems to be what {i.*} expects. Now I have the following question:

  • The exact naming of the subtype alias joins that Hibernate expects feels like an implementation detail, which I’m not sure if my query should be concerned about. Thus, I’m wondering if my approach is correct or if I missed some way where I can tell Hibernate the alias per subtype to expect.

The query does work, and the alias names seem to be stable, but I can already see that this breaks when I upgrade the Hibernate version. As I’m currently working on a legacy application, I have to use Hibernate version 5.6.15.Final for now. The documentation about inheritance in native queries also does not contain more hints.

2

This is simply a limitation of the current API. You should be able to use select * or select i.*, i_1_.*, ... instead to avoid the aliasing problem, assuming you have no two columns in different tables with the same name.

3

Unfortunately, I have some columns with the same names. So I guess as long as the assigned numbers in the subtype table aliases are deterministic, this is ok.

4

The names are deterministic, yes.

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