JHipster Post REST API显示SQL错误

Question

我正在使用JHipster创建一个项目。 我有2个实体（课程，学生），并且它们具有多对多关系。 因此，还有另一个名为Course_Student的实体，它具有2列（student_id，course_id）。 学生（用户）需要通过单击自己面板上的“注册课程”按钮来注册课程。 所以我写了一个查询和休息API函数。

这是我的查询功能：

@Modifying
@Query(value="insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (:studentId,:courseId)",nativeQuery = true) 
@Transactional
void registerCourse(@Param("studentId") Long studentId, @Param("courseId") Long courseId);

和Rest API函数：

@PostMapping("/registercourse/{studentId}/{courseId}")
@Timed
public ResponseEntity<Void> registerCourse(@PathVariable Long studentId,@PathVariable Long courseId) {
    log.debug("REST request to register {} Course : {} Student : {}", courseId,studentId);
    courseRepository.registerCourse(studentId,studentId);
    return ResponseEntity.ok().headers(HeaderUtil.createEntityCreationAlert(ENTITY_NAME, courseId.toString())).build();
}

但是，当我尝试使用Swagger控制台运行registerCourse API时，显示以下错误：（我输入的学生ID：33，课程ID：1）

c.m.m.w.rest.errors.ExceptionTranslator  : An unexpected error occurred: could not execute statement; SQL [n/a]; constraint ["FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint ["FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
        at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:278)
Caused by: org.hibernate.exception.ConstraintViolationException: could not execute statement
        at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:112)
        ... 145 common frames omitted
Caused by: org.h2.jdbc.JdbcSQLException: Referential integrity constraint violation: "FK_COURSE_STUDENT_COURSES_ID: PUBLIC.COURSE_STUDENT FOREIGN KEY(COURSES_ID) REFERENCES PUBLIC.COURSE(ID) (33)"; SQL statement:
insert into COURSE_STUDENT (STUDENTS_ID, COURSES_ID) VALUES (?,?) [23506-196]
        at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)
        ... 163 common frames omitted
2017-09-08 08:58:57.099  WARN 7528 --- [  XNIO-2 task-8] .m.m.a.ExceptionHandlerExceptionResolver : Resolved exception caused by Handler execution: org.springframework.

Answer 1

您正在将student_id作为course_id传递，并且不存在ID为33的课程。请参见Rest API的registerCourse的第三行：

    courseRepository.registerCourse(studentId,studentId);

改成：

    courseRepository.registerCourse(studentId,courseId);