級聯上的Hibernate /春數據刪除

Question

我有以下實體：

@Entity 
public class Car { ... } 

@Entity 
public class Driver { 
    @ManyToOne(cascade=CascadeType.ALL) 
    @JoinColumn(name = "CAR_ID") 
    private Car car; 

    ... 
} 

@Entity 
public class Penalty { 
    @ManyToOne(cascade=CascadeType.ALL) 
    @JoinColumn(name="D_ID") 
    private Driver driver; 

    ... 
} 

我想從Driver和Penalty當Car爲carRepository.delete(car_id)被刪除刪除所有信息。

WARN : org.hibernate.engine.jdbc.spi.SqlExceptionHelper - SQL Error: 1451, SQLState: 23000 
ERROR: org.hibernate.engine.jdbc.spi.SqlExceptionHelper - Cannot delete or update a parent row: a foreign key constraint fails (`test`.`car_drivers`, CONSTRAINT `FK9ux9oqx6yr66cva4ro6l8m63r` FOREIGN KEY (`CAR_ID`) REFERENCES `cars` (`CAR_ID`)) 
ERROR: org.hibernate.internal.ExceptionMapperStandardImpl - HHH000346: Error during managed flush [org.hibernate.exception.ConstraintViolationException: could not execute statement] 
ERROR: com.app.cars.controller.AdminController - Exception during deleting car due to could not execute statement; SQL [n/a]; constraint [null]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement 

無法更改表屬性和設計。所以，需要通過修復實體模型來擺脫這個錯誤。

Answer 1

您的實體模型不會級聯刪除到Driver，然後到Penalty，因此數據庫將引發約束違規錯誤。該模型應該如下：

@Entity 
class Car { 
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "car", orphanRemoval = true) 
    private Set<Driver> drivers; 

    ... 
} 

@Entity 
class Driver { 
    @ManyToOne 
    private Car car; 

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "driver", orphanRemoval = true) 
    private Set<Penalty> penalties; 

    ... 
} 

@Entity 
class Penalty { 
    @ManyToOne 
    private Driver driver; 

    ... 
}