问题
I have two tables in my database: sliders and images. One slider can have many images, so the structure of tables is:
--------- --------
| SLIDERS | | IMAGES |
--------- --------
| id | | id |
--------- --------
| title | | title |
--------- --------
| sid |
--------
SID is a foreign key associated to id in "SLIDERS" table.
In entities I put bidirectional relationships OneToMany and ManyToOne, so fetched Slider result would contain Images Objects that belong to him, and Images would contain Slider Object that belongs to them.
Sliders Entity:
class Sliders
{
...
/**
* @ORM\OneToMany(targetEntity="Images", mappedBy="slider")
*/
protected $images;
Images Entity:
class Images
{
...
/**
* @ORM\ManyToOne(targetEntity="Sliders", inversedBy="images")
* @ORM\JoinColumn(name="sid", referencedColumnName="id")
*/
protected $slider;
It is really comfortable for fetching. But now I can't understand how can I INSERT sid into Images table, since I don't have this field in my entity except $slider that returns Object. Is it possible to do it using this $slider?
回答1:
Following function you should have already in your Slider entity (or similar).
public function addImage(Image $image)
{
$image->setSlider($this); // This is the line you're probably looking for
$this->images[] = $image;
return $this;
}
What it does is if you persist the entity it writes the ID of the Slider (sid) into your Image.
来源：https://stackoverflow.com/questions/26653862/doctrine-how-to-insert-foreign-key-value