如何找到对象字段

Question

我有位置，我想要按公司

检索数据库中的所有位置

我可以这样做List<Location> findByCompanyId(Long companyId);

但我如何检索地点的ID而不是整个对象

 List<Long> findByCompanyId(Long companyId);

我想要与第一种方法相同的东西，但没有整个对象只有ids

public class Location extends BaseEntity {

@Column(name = "`street_first`", nullable = false)
private String streetFirst;

@Column(name = "`street_second`")
private String streetSecond;

@Column(name = "`city`", nullable = false)
private String city;

@Column(name = "`zip`")
private String zip;

@Column(name = "`state`", nullable = false)
private String state;

@Column(name = "`phone`", nullable = false)
private String phone;

@JoinColumn(name = "`company_id`", nullable = false)
private Company company;
}
//getters and setters

Answer 1

@Query("SELECT l.id FROM Location l WHERE l.company.id = :companyId");
List<Long> getLocationIds(@Param("companyId")Long companyId);