How to make entity without id symfony?

Question

symfony

/**
 * @ORM\Entity
 * @ORM\Table(name="settings")
 */
class SettingsEntity
{

    /**
     * @Assert\NotBlank()
     * @ORM\Column(name="key", type="string", length=255)
     */
    public $key;

    /**
     * @Assert\NotBlank()
     * @ORM\Column(name="value", type="text")
     */
    public $value;

}

No identifier/primary key specified for Entity "AdminBundle\Entity\SettingsEntity". Every Entity must have an identifier/primary key.

How to make key as primary key in entity?
Key will not change, values ​​will only change in value

Answer 1

RTFM . The phrase "Every entity class must have an identifier/primary key" seems to hint.