Problem:
When a WITH condition for a LEFT OUTER JOIN of a map relation, which is mapped with a collection table, filters results by KEY the resulting query is wrong in my opinion.

HQL:

SELECT 
	d.id 
FROM 
	Document d 
LEFT JOIN 
	d.contacts c 
		WITH KEY(c) = 1

Generated SQL:

select
	document0_.id as col_0_0_ 
from
	Document document0_ 
left outer join
	Document_Person contacts1_ 
		on document0_.id=contacts1_.Document_id 
left outer join
	Person person2_ 
		on contacts1_.contacts_id=person2_.id 
		and (
			contacts1_.position=1
		)

Hibernate 4.2.7.SP1 and below moved the condition "contacts1_.position=1" into the collection table join.
Hibernate 4.2.8.Final+ always puts the condition in the second join.

Solution:
If such a WITH condition occurs, an additional where-condition has to be added. The where-condition has to be like ALIAS_FOR_VALUE_TABLE.ID IS NOT NULL where ALIAS_FOR_VALUE_TABLE is the name of the table, which contains the values of the map.

Corrected generated SQL:

select
	document0_.id as col_0_0_ 
from
	Document document0_ 
left outer join
	Document_Person contacts1_ 
		on document0_.id=contacts1_.Document_id 
left outer join
	Person person2_ 
		on contacts1_.contacts_id=person2_.id 
		and (
			contacts1_.position=1
		)
where
	person2_.id IS NOT NULL

To summarize, this where-condition, only has to be added if

• an on-condition contains a KEY expression for the joined relation
• in a left outer join
• of indexed(map- or list-attribute)-attributes
• where the map-key-column or order-column is located in a collection table