不在子查询中更改为 HQL 中的左外连接

问题描述

我有以下 HQL

select distinct(ordr) 
from OfOrder ordr,SalesChannel sc  
where  
   ordr.status in (:statusList) and 
   ordr.ofOrderId not in (
          select ordrLabel2.ofOrder.ofOrderId 
          from OrderLabel ordrLabel2 
          where 
             ordrLabel2.ofLabel.labelId in ( :ofLabels )
          ) and 
  ordr.orderMain.salesChannel.channelId in (:channelIds)  and 
  ordr.deliveryChannel.deliveryChannelId in (:deliveryChannels) 
order by ordr.deliveryDate asc,CASE   
  when ordr.status = 'SU' then 1 
  when ordr.status = 'SU' then 1 
  when ordr.status = 'SU' then 1 
  when ordr.status = 'AC' then 2 
  when ordr.status = 'AC' then 2 
  when ordr.status = 'AC' then 2 
  when ordr.status = 'AC' then 3 
  when ordr.status = 'AC' then 4 
  when ordr.status = 'AC' then 4 
  when ordr.status = 'SH' then 5 
  when ordr.status = 'SH' then 5 
  when ordr.status = 'DD' then 6 
  when ordr.status = 'R' then 7 
  when ordr.status = 'C' then 8 
  ELSE 9999    
END

Hibernate 生成了以下相同的查询

select distinct oforder0_.`of_order_id`
as of_order1_27_,oforder0_.`assigned_to`
as assigned2_27_,oforder0_.`Box_size`
as Box_size3_27_,oforder0_.`Boxes`
as Boxes4_27_,oforder0_.`created_date`
as created_5_27_,oforder0_.`delivery_channel_id`
as deliver25_27_,oforder0_.`delivery_channel_order_id`
as delivery6_27_,oforder0_.`delivery_date`
as delivery7_27_,oforder0_.`delivery_labelled`
as delivery8_27_,oforder0_.`delivery_status`
as delivery9_27_,oforder0_.`description`
as descrip10_27_,oforder0_.`display_name`
as display11_27_,oforder0_.`fulfillment_center_id`
as fulfill26_27_,oforder0_.`kitchen_labelled`
as kitchen12_27_,oforder0_.`message`
as message13_27_,oforder0_.`group_id`
as group_i27_27_,oforder0_.`shipping_address_id`
as shippin28_27_,oforder0_.`order_main_id`
as order_m29_27_,oforder0_.`order_type`
as order_t14_27_,oforder0_.`packing_priority`
as packing15_27_,oforder0_.`quantity`
as quantit16_27_,oforder0_.`requiresShipping`
as require17_27_,oforder0_.`shipping_line_id`
as shippin30_27_,oforder0_.`split_number`
as split_n18_27_,oforder0_.`status`
as status19_27_,oforder0_.`total_price`
as total_p20_27_,oforder0_.`tracking_id`
as trackin21_27_,oforder0_.`updated_date`
as updated22_27_,oforder0_.`vendor_id`
as vendor_23_27_,oforder0_.`vendor_name`
as vendor_24_27_
from `of_order` oforder0_
cross join `sales_channel` saleschann1_
    cross join `order_main` ordermain3_
where oforder0_.`order_main_id`=ordermain3_.`order_main_id`
        and (oforder0_.`status` in ('SU','AC'))
        and (oforder0_.`of_order_id`
        not in  (
select orderlabel2_.`of_order_id`
            from `order_label` orderlabel2_
            where orderlabel2_.`label_id`
            in (29,37)
            )
)
and (ordermain3_.`channel_id`
in (1,4)
            )
        and (oforder0_.`delivery_channel_id`
in (2,5)
            )
order by oforder0_.`delivery_date` asc,case
when oforder0_.`status`='SU' then 1
        when oforder0_.`status`='SU' then 1
        when oforder0_.`status`='SU' then 1
        when oforder0_.`status`='AC' then 2
        when oforder0_.`status`='AC' then 2
        when oforder0_.`status`='AC' then 2
        when oforder0_.`status`='AC' then 3
        when oforder0_.`status`='AC' then 4
        when oforder0_.`status`='AC' then 4
        when oforder0_.`status`='SH' then 5
        when oforder0_.`status`='SH' then 5
        when oforder0_.`status`='DD' then 6
        when oforder0_.`status`='R' then 7
        when oforder0_.`status`='C' then 8
        else 9999
end
limit 50,50;

上面的查询给出了我需要的确切结果。但我认为连接查询会提高性能。如果不是，请纠正我。怎么做我需要将子查询部分更改为左外连接

（选择 ordrLabel2.ofOrder.ofOrderId from OrderLabel ordrLabel2 where ordrLabel2.ofLabel.labelId in (:ofLabels)

如何通过外连接实现相同的结果。我需要一个带有左外连接的上述结果的 HQL 有人请帮助我实现这一目标

解决方法

如果你需要性能，不要依赖 hql/sql 转换，使用原生查询，不要选择所有字段，而只选择一个你真正需要的字段。

另一种策略是在您的数据上构建一个视图（也研究物化视图），然后在其上构建 hql / sql，这样您就可以拥有更简单的数据模型、良好的性能和对如何处理数据的精细控制您的数据库。

如果使用 left join 而不是 cross join 有意义，您可以将查询更改为 this ，对于您的 order by ，您也可以简化它：

ClassCastException

hql java java mysql