Entity containing other entities without having a table - symfony

Question

I have an Entity ( Invoice ) which is purely for calculation purposes and has no table, that associates with two other entities having relations by tables. (Although there are so many other entities involved ).
class Row{
/**
* #var integer
*
* #ORM\Column(name="row_id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #ORM\ManyToOne(targetEntity="File")
* #ORM\JoinColumn(name="file_id", referencedColumnName="file_id")
*/
protected $file;
/**
* #var \DateTime
*
* #ORM\Column(name="date", type="date")
*/
private $date;
}
class File
{
/**
* #var integer
*
* #ORM\Column(name="file_id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="name", type="string", length=255)
*/
private $name;
}
class Invoice
{
/**
* #ORM\Id
* #ORM\Column(name="invoice_id", type="integer")
* #ORM\GeneratedValue
*/
protected $id = null;
/**
* #ORM\OneToMany(targetEntity="Row", mappedBy="row_id")
*/
protected $row;
/**
* #ORM\OneToMany(targetEntity="File", mappedBy="file_id")
*/
protected $file;
}
I want to be able to query for Invoices :
$sDate = //Some date
$this->getEntityManager()
->createQuery("SELECT Invoice, Row, File
FROM
ReportsEntitiesBundle:Invoice Invoice
LEFT JOIN
Row.row Row
LEFT JOIN
Row.file File
WHERE date=:date"
)
->setParaMeter(':date', $sDate)
->setFirstResult($iPage*$iLimit)
->setMaxResults($iLimit)
->getResult();
The questions :
# Doctrine tries to query the database, how can I prevent that and have it find the relevant entities?
# How can I relate the date ( which is in Row entity and cannot be in Invoice ) to the query?
Later this Invoice will become a part of another big entity for calculating/search purposes.
Thank you

Answer 1

Short Answer: You can't
Long Answer : You can't because an entity with #ORM annotations means its persisted to a database - querying that entity relates to querying a database table. Why not just create the table ?!?!?
You need somewhere to persist the association between file and row - a database table is a perfect place !!!!
Update
Just to clarify ... an Entity is just a standard class - it has properties and methods ... just like any other class - When you issue doctrine based commands it uses the annotations within the entities to configure the tables / columns / relationships etc if remove those you can use it however you like ... but you will need to populate the values to use it and you wont be able to use it in a Doctrine query and it obviously wont be persisted !

Answer 2

You can use a read-only entity. It's contents are backed by a view which you create manually in SQL.
PHP:
/** #ORM\Entity(readOnly =true) */
class InvoiceView
{ ...
SQL:
CREATE VIEW invoice_view AS (
SELECT ...