App\Entity\Hero:
    type: entity
    repositoryClass: App\Entity\Repository\HeroRepository
    table: hero
    id:
        id:
            type: integer
            generator: { strategy: AUTO }
    fields:
        name:
            type: string
            length: 32
            unique: true

    manyToOne:
        user:
            targetEntity: User
            inversedBy: heroes
            joinColumn:
                onDelete: CASCADE
                nullable: false