In Doctrine 2/Symfony 3 with Postgres as the database I am trying to create a table with following fields:
**actions-reviews**
id
action_id
action_task_id
document_id
review_to
review_date
review_description
review_by
is_effective
The table is either linked to a doc_id which is foreign key for an entity called Document or action_task_id for entity called ActionTask. In order to achieve this I am using inheritance mapping via the use of discriminator. In skipper the entity relationship look like this: 
As you can see both the ActionTask and ActionReview are sub-set of Action entity.
My issue is when create the entities and run php bin/console doctrine:schema:update --force I get the following error:
[Doctrine\ORM\Mapping\MappingException]
No identifier/primary key specified for Entity "AppBundle\Entity\ActionTask
Review". Every Entity must have an identifier/primary key.
Reading the forums I add @ORM/Id to ActionTaskReview entity and then it updates the DB without any errors. However when I look at the postgres table only the document_id field is there not the action_task_id field. What I am doing wrong as the document_id does not throw the same error when I exclude @ORM/Id?
My Doctrine entities look like: ActionReview.php
/**
* @ORM\Entity
* @ORM\Table(name="actions_reviews")
* @ORM\InheritanceType("SINGLE_TABLE")
* @ORM\DiscriminatorColumn(name="owner", type="string")
* @ORM\DiscriminatorMap({"document":"AppBundle\Entity\DocumentActionReview","action_task":"AppBundle\Entity\ActionTaskReview"})
* @Discriminator(field = "owner", map = {"document": "AppBundle\Entity\DocumentActionReview", "action_task": "AppBundle\Entity\ActionTaskReview"})
*/
abstract class ActionReview
{
/**
* @ORM\Id
* @ORM\Column(type="guid")
* @ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* @ORM\Column(type="datetime", nullable=true)
*/
private $review_date;
/**
* @ORM\Column(type="text", nullable=true)
*/
private $review_description;
/**
* @ORM\Column(type="boolean", nullable=true)
*/
private $is_effective;
/**
* @ORM\ManyToOne(targetEntity="AppBundle\Entity\Action", inversedBy="action_review")
* @ORM\JoinColumn(name="action_id", referencedColumnName="id")
*/
private $action;
/**
* @ORM\ManyToOne(targetEntity="AppBundle\Entity\Employee")
* @ORM\JoinColumn(name="review_to", referencedColumnName="id")
*/
private $review_to;
/**
* @ORM\ManyToOne(targetEntity="AppBundle\Entity\Employee")
* @ORM\JoinColumn(name="review_by", referencedColumnName="id")
*/
private $review_by;
/**
* Get id
*
* @return guid
*/
public function getId()
{
return $this->id;
}
/**
* Set reviewDate
*
* @param \DateTime $reviewDate
*
* @return ActionReview
*/
public function setReviewDate($reviewDate)
{
$this->review_date = $reviewDate;
return $this;
}
/**
* Get reviewDate
*
* @return \DateTime
*/
public function getReviewDate()
{
return $this->review_date;
}
/**
* Set reviewDescription
*
* @param string $reviewDescription
*
* @return ActionReview
*/
public function setReviewDescription($reviewDescription)
{
$this->review_description = $reviewDescription;
return $this;
}
/**
* Get reviewDescription
*
* @return string
*/
public function getReviewDescription()
{
return $this->review_description;
}
/**
* Set isEffective
*
* @param boolean $isEffective
*
* @return ActionReview
*/
public function setIsEffective($isEffective)
{
$this->is_effective = $isEffective;
return $this;
}
/**
* Get isEffective
*
* @return boolean
*/
public function getIsEffective()
{
return $this->is_effective;
}
/**
* Set action
*
* @param \AppBundle\Entity\Action $action
*
* @return ActionReview
*/
public function setAction(\AppBundle\Entity\Action $action = null)
{
$this->action = $action;
return $this;
}
/**
* Get action
*
* @return \AppBundle\Entity\Action
*/
public function getAction()
{
return $this->action;
}
/**
* Set reviewTo
*
* @param \AppBundle\Entity\Employee $reviewTo
*
* @return ActionReview
*/
public function setReviewTo(\AppBundle\Entity\Employee $reviewTo = null)
{
$this->review_to = $reviewTo;
return $this;
}
/**
* Get reviewTo
*
* @return \AppBundle\Entity\Employee
*/
public function getReviewTo()
{
return $this->review_to;
}
/**
* Set reviewBy
*
* @param \AppBundle\Entity\Employee $reviewBy
*
* @return ActionReview
*/
public function setReviewBy(\AppBundle\Entity\Employee $reviewBy = null)
{
$this->review_by = $reviewBy;
return $this;
}
/**
* Get reviewBy
*
* @return \AppBundle\Entity\Employee
*/
public function getReviewBy()
{
return $this->review_by;
}
}
ActionTaskReview.php
namespace AppBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
use JMS\Serializer\Annotation\Exclude;
/**
* ActionTaskReview
* @ORM\Entity
*/
class ActionTaskReview
{
/**
* @ORM\ManyToOne(targetEntity="AppBundle\Entity\ActionTask", inversedBy="action_review")
* @ORM\JoinColumn(name="action_task_id", referencedColumnName="id") \AppBundle\Entity\ActionTask
*/
private $action_task;
/**
* Set actionTask
*
* @param \AppBundle\Entity\ActionTask $actionTask
*
* @return ActionTaskReview
*/
public function setActionTask(\AppBundle\Entity\ActionTask $actionTask = null)
{
$this->action_task = $actionTask;
return $this;
}
/**
* Get actionTask
*
* @return \AppBundle\Entity\ActionTask
*/
public function getActionTask()
{
return $this->action_task;
}
}
DocumentActionReview.php
<?php
namespace AppBundle\Entity;
use Doctrine\ORM\Mapping as ORM;
/**
* @ORM\Entity
* @ORM\Table(name="documents_actions_reviews")
*/
class DocumentActionReview extends \AppBundle\Entity\ActionReview
{
/**
* @ORM\ManyToOne(targetEntity="AppBundle\Entity\Document", inversedBy="action_review")
* @ORM\JoinColumn(name="document_id", referencedColumnName="id")
*/
private $document;
/**
* Set document
*
* @param \AppBundle\Entity\Document $document
*
* @return DocumentActionReview
*/
public function setDocument(\AppBundle\Entity\Document $document = null)
{
$this->document = $document;
return $this;
}
/**
* Get document
*
* @return \AppBundle\Entity\Document
*/
public function getDocument()
{
return $this->document;
}
}
