Efficiently inserting parent and children one-to-many

Issue type:

[x] question

Database system/driver:

[x] postgres

TypeORM version:

[x] latest

I have the following code that works as expected but I am unsure if this is the most efficient solution.

        // Insert release
        const release = Release.create(input);
        await release.save();

        // Assign each track the release ID
        const tracks = input.tracks.map(track => ({
          ...track,
          releaseId: release.id,
        }));

        // Bulk insert tracks
        await getConnection()
          .createQueryBuilder()
          .insert()
          .into(Track)
          .values(tracks)
          .execute();

I would like to be able to insert a parent (Release) and its multiple children (Track) in one operation. I’m not sure if I have missed something in the documentation, or if this is just not possible. Thanks

Release entity:

@Entity('releases')
export class Release extends BaseEntity {
  @PrimaryGeneratedColumn('uuid')
  id: string;

  @OneToMany(() => Track, track => track.release)
  tracks: Track[];
}

Track entity:

@Entity('tracks')
export class Track extends BaseEntity {
  @PrimaryGeneratedColumn('uuid')
  id: string;

  @Column({ type: 'uuid', name: 'release_id' })
  releaseId: string;

  @ManyToOne(() => Release, release => release.tracks)
  @JoinColumn({ name: 'release_id' })
  release: Release;
}

[LordShiroe]

I have the same question! I thought that setting { cascade: true} in the relation would do the trick but no, it tries to save the children without the parent id even if it already knows it. For now, I’m going to use the snippet shared here.

[jtownsley]

I think you may need to add the cascade: ['insert'] option to to your parent relation, like this @OneToMany(() => Track, track => track.release, { cascade: ['insert'] }). That should allow you to save the release and automatically associate the child Tracks to it.