Can I eager load a property using HQL?
I'm tryi开发者_开发知识库ng to work out how to eager load the customers in the following HQL query:
select order.Customer
from Order as order
where order.Id in
(
select itemId
from BadItem as badItem
where (badItemType = :itemType) and (badItem.Date >= :yesterday)
)
There's the usual many-to-one relationship between orders and customers.
I'd like to do this is in the query, as opposed to the mapping, if possible - as in a "join fetch..."
Maybe the query would be refactored as a join and I'm having a mental block.
Any ideas?
select customer
from BadItem as badItem
join fetch badItem.Order as order
left join fetch order.Customer as customer
where (badItemType = :itemType) and (badItem.Date >= :yesterday)
For this to work you will need to add the relationship between BadItem and Order if BadItem is unrelated to Order, or use an inner join
with extra conditions (watch out for performance when using alternative 2).
Alternative:
select customer
from Order as order
join fetch order.Customer as customer
where order.Id in
(
select itemId
from BadItem as badItem
where (badItemType = :itemType) and (badItem.Date >= :yesterday)
)
EDIT:
What about:
select customer
from Order as order
join fetch order.Customer customer
join fetch customer.orders
where order.Id in
(
select itemId
from BadItem as badItem
where (badItemType = :itemType) and (badItem.Date >= :yesterday)
)
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