from model.teacher_model import TeacherCourse


def add_teacher_course_dao(t,db):
    try:   #判断是都已存在
        r = db.query(TeacherCourse).filter(TeacherCourse.teacher_id==t['teacher_id']).first()
        if r:
            return None   #已存在，交给上层判断
        obj = TeacherCourse(**t)
        db.add(obj)
        db.commit()
        db.refresh(obj)  #拿回自增id，create_time等
        return obj
    except Exception:
        db.rollback()
        return False


def get_teacher_course_dao(teacher_id=None,db=None):
    q = db.query(TeacherCourse)
    if teacher_id:
        q = q.filter(TeacherCourse.teacher_id==teacher_id)
    return q.all()   #返回ORM对象列表