HQL left join of un-related entities

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Currently, the theta-style on joining the unrelated classes in the where clause using HQL only supports inner join.

The request for supporting the outer join for such situation is currently the 3-rd most voted enhancement but I don’t think this feature will be implemented in the near feature as it requires the re-implementation of the current ANTLER-based query parser first which seems to be a gigantic task IMO.

If you insist to use the HQL to perform left join without adding the relationship between A and B , you can use option 3 to do the inner join first, then use the following HQL 

from A a where a.some not in ( select b.some from B)

to find out all the A that cannot join B and combine the results programmatically .

Update

As of release 5.1.0 HHH-16 (Explicit joins on unrelated classes) is fixed and we should be able to join the unrelated entities.

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