Spring Data JPA本机查询返回1个实体，而不是一个List

Question

I have query (always return List has 1 SysAutoId )

@Query(value = "SELECT * FROM SYSAutoID WHERE RefTypeCategory = ?1 AND BranchID = ?2 ", nativeQuery = true)
List<SysAutoId> findSpecific(Integer refTypeCategory, Integer branchId);

I want create a method like

@Query(value = "SELECT * FROM SYSAutoID WHERE RefTypeCategory = ?1 AND BranchID = ?2 ", nativeQuery = true)
SysAutoId findSpecific(Integer refTypeCategory, Integer branchId);

return one entity, how to do that?

Answer 1

The return type should be Optional of Entity because it only returns the first matching record, look at the syntax of findById method

Optional<T> findById(ID primaryKey)

Code

@Query(value = "SELECT * FROM SYSAutoID WHERE RefTypeCategory = ?1 AND BranchID = ?2 ", nativeQuery = true)
Optional<SysAutoId> findSpecific(Integer refTypeCategory, Integer branchId);