backend/src/entities/user-course.entity.ts

import {
  Entity,
  Column,
  PrimaryGeneratedColumn,
  CreateDateColumn,
  ManyToOne,
  JoinColumn,
  Index,
} from 'typeorm';
import { User } from './user.entity';
import { Course } from './course.entity';

@Entity('user_courses')
@Index(['userId', 'courseId'], { unique: true })
export class UserCourse {
  @PrimaryGeneratedColumn()
  id: number;

  @Column({ name: 'user_id' })
  userId: number;

  @Column({ name: 'course_id' })
  courseId: number;

  @Column({ type: 'varchar', length: 64, unique: true, name: 'access_token' })
  accessToken: string;

  @Column({ type: 'datetime', name: 'expired_at' })
  expiredAt: Date;

  @CreateDateColumn({ name: 'created_at' })
  createdAt: Date;

  @ManyToOne(() => User, (user) => user.userCourses)
  @JoinColumn({ name: 'user_id' })
  user: User;

  @ManyToOne(() => Course, (course) => course.userCourses)
  @JoinColumn({ name: 'course_id' })
  course: Course;
}