假设我有实体(为简洁起见,省略了getter / setter和各种细节):
@Entity
class Customer{
...
@OneToMany(cascade = CascadeType.ALL, mappedBy = "customer")
Collection<Coupon> coupons;
}
@Entity
class Coupon{
...
@Temporal(value = TemporalType.TIMESTAMP)
private Date usedOn;
@ManyToOne(fetch = FetchType.LAZY)
@NotNull
Customer customer;
}
我希望为null为null的给定客户检索所有优惠券。
我尚未按照docs中的说明在CouponRepository中定义一个方法,但未成功
@Repository
public interface CouponRepository extends CrudRepository<Coupon, Long> {
Collection<Coupon> findByCustomerAndUsedOnIsNull(Customer);
}
但这会导致编译器错误
Syntax error, insert "... VariableDeclaratorId" to complete FormalParameterList
。 最佳答案
我的错,正确的定义是
@Repository
public interface CouponRepository extends CrudRepository<Coupon, Long> {
Collection<Coupon> findByCustomerAndUsedOnIsNull(Customer customer);
}
我只是错过了参数名称:-(
关于spring - Spring数据查询,其中column为空,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/29448282/