如何包含冗余列以显示在 SELECT 从第二个表而不是从 Spring 存储库中的主表查询？

Question

I have a query like this: Query 1:

select *
from items item

This is bind to an entity in SpringJPA. Now I have to select one more column from another table like below.

Query 2:

select item.*,is.id
from items item
inner join item_state itm_s where item.id=itm_s.id

Now,there is a column "code" which exists in both item and item_state. I want to select it from item_state and not from item due to some data issues. I know the straight forward way is to write all columns in select statement,excluding code column from item and including code column from item_state. But the thing is item table has around 100 columns. Is there a good way to solve this issue without changing the entity class?

Answer 1

Look at Spring Data JPA projections and perform the following query:

@Query("select item.*, itm_s.code from items item join item.item_state itm_s where item.id = itm_s.id")

You will have to look at the resulting query to write your projection class.