Spring Data-JPA：使用DTO和IF语句发出查询

Question

I am trying to make a query that would build a DTO object :

@Query("Select new com.mycorp.rh.web.rest.dto.AnalyseProductionDTO(a.client.name, IF(a.salarie,'yes','no'))   
from Activity a where a.year = ?1 and a.month = ?2")
        List<AnalyseProductionDTO> getAnalyseProduction(Year year, Month month);

It doesn't work when I put a IF statement in the query.
I am getting a

java.lang.IllegalArgumentException: Validation failed for query

It works when I do :

@Query("Select new com.mycorp.rh.web.rest.dto.AnalyseProductionDTO(a.client.name, 'yes')   
from Activity a where a.year = ?1 and a.month = ?2")
        List<AnalyseProductionDTO> getAnalyseProduction(Year year, Month month);

Isn't it possible to include an IF statement in a constructor used in a query?

Answer 1

By default @Query doesn't allow native queries. The query should be either HQL if the ORM is hibernate or anything that is supported by the underlying ORM.

Since IF() function is native to MySQL and not supported by ORM query languages its validation will fail.

You can try the following with @Query.nativeQuery set to true .

@Query(value = "Select new com.mycorp.rh.web.rest.dto.AnalyseProductionDTO(a.client.name, IF(a.salarie,'yes','no'))   
from Activity a where a.year = ?1 and a.month = ?2", nativeQuery = true)