nhibernate - 我可以使用 HQL 预先加载属性吗？

Question

我正在尝试解决如何在以下 HQL 查询中急切加载客户:

select order.Customer
from Order as order
where order.Id in
(
  select itemId
  from BadItem as badItem
  where (badItemType = :itemType) and (badItem.Date >= :yesterday)
)

订单和客户之间通常存在多对一的关系。

如果可能的话，我想在查询中执行此操作，而不是在映射中 - 如在“join fetch ...”中

也许查询会被重构为一个连接，我有一个心理障碍。

有任何想法吗？

Answer 1

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)

为此，如果 BadItem 与 Order 无关，您需要添加 BadItem 和 Order 之间的关系，或者使用 inner join有额外的条件(使用备选方案 2 时注意性能)。

选择:

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)
)

编辑:

关于什么:

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)
)