Fetch entity without related objects doctrine - php

I have the following classes:
class Category {
/**
* #ORM\OneToMany(targetEntity="Product", mappedBy="category")
*/
private $products;
...
}
class Product {
...
/**
* #ORM\ManyToOne(targetEntity="Category", inversedBy="products")
* #ORM\JoinColumn(name="category_id", referencedColumnName="id")
*/
private $category;
...
}
when i try to fetch one product from my db like this:
$query = $doctrineManager->createQuery(
"
SELECT p FROM AppBundle:Product p
WHERE p.id = :id
"
)->setParameter('id', $id);
$result = $query->getSingleResult();
i get not only my product, but also get category with all products (except the one i found). So, how can i fetch only model what i want without any related model?

They are just stubs, you don't actually fetch any related entity information unless you are using fetch=EAGER.
This answer explains it pretty well.
What is the difference between fetch="EAGER" and fetch="LAZY" in doctrine
In summary, you can't get rid of the associations, but they don't load the other entities until you call the data unless you specifically request otherwise. So don't worry about it.

Related

How does inner join work on a many-to-many relationship using Doctrine and Symfony2

I recently worked out an issue with querying ManyToMany relationship join tables, the solution was same as this answer and was wondering how it works.
lets say i have a simple ManyToMany relationship between groups and team, there will be a groups_team tables that will automatically be created here
groups entity
/**
* Groups
*
* #ORM\Table(name="groups")
* #ORM\Entity(repositoryClass="AppBundle\Model\Repository\GroupsRepository")
*/
class Groups {
/**
* #ORM\ManyToMany(targetEntity="Team", inversedBy="group")
*/
protected $team;
public function __construct() {
$this->team = new ArrayCollection();
}
/**
* #var int
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="groupname", type="string", length=255)
*/
private $groupname;
//obligatory getters and setters :)
team entity
/**
* Team
*
* #ORM\Table(name="team")
* #ORM\Entity(repositoryClass="AppBundle\Model\Repository\TeamRepository")
*/
class Team {
/**
* #ORM\ManyToMany(targetEntity="Groups", mappedBy="team")
*/
protected $group;
public function __construct(){
$this->group = new ArrayCollection();
}
/**
* #var int
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var string
*
* #ORM\Column(name="teamname", type="string", length=255)
*/
private $team;
//[setters and getters here]
in order to get all the teams in a group i would have to query the groups_team table.i would have directly queried the table in just mysql but in symfony i have to do this
$groups = $em->getRepository("AppBundle\Model\Entity\Groups")->findBy(array('tournament' => $tournament->getId()));
//get all teams with group id in groups_team table
foreach ($groups as $group) {
$teamsingroup = $em->getRepository("AppBundle\Model\Entity\Team")->createQueryBuilder('o')
->innerJoin('o.group', 't')
->where('t.id = :group_id')
->setParameter('group_id', $group->getId())
->getQuery()->getResult();
echo "</b>".$group->getGroupname()."</b></br>";
foreach ($teamsingroup as $teamingroup) {
echo $teamingroup->getTeam()."</br>";
}
}
Can someone explain to me how the innerJoin is working and what is the concept behind this, maybe a few documentation to learn about this. are there better way to do this with symfony and doctrine.
Using ManyToMany between 2 entities involves a third table generally called as a junction table in this type of relation when you build a DQL (doctrine query) doctrine automatically joins junction table depending on the nature of relation you have defined as annotation so considering your query
$teamsingroup = $em->getRepository("AppBundle\Model\Entity\Team")
->createQueryBuilder('o')
->innerJoin('o.group', 't')
You are joining Team entity with Group entity in innerJoin('o.group') part o is the alias for Team entity and o.group refers to property defined in Team entity named as group.
/**
* #ORM\ManyToMany(targetEntity="Groups", mappedBy="team")
*/
protected $group;
Which has a ManyToMany annotation defined for this type of relation doctrine joins your team table first with junction table and then joins your junction table with groups table and the resultant SQL will be something like
SELECT t.*
FROM teams t
INNER JOIN junction_table jt ON(t.id = jt.team_id)
INNER JOIN groups g ON(g.id = jt.group_id)
WHERE g.id = #group_id
Another thing related your way of getting team for each group you can minimize your code by excluding createQueryBuilder part within loop, once you have defined teams property as ArrayCollection i.e $this->team = new ArrayCollection(); on each group object you will get collections of teams associated to that particular group by calling getTeam() function on group object similar to below code.
foreach ($groups as $group) {
$teamsingroup = $group->getTeam();
echo "</b>".$group->getGroupname()."</b></br>";
foreach ($teamsingroup as $teamingroup) {
echo $teamingroup->getTeam()."</br>";
}
}
I guess it's literally select statement with INNER JOIN using key columns defined entity class as mappedBy or inversedBy.
Why don't you have a look of doctrine log and see what the native sql is composed?
How to get Doctrine to log queries in Symfony2 (stackoverflow)
http://vvv.tobiassjosten.net/symfony/logging-doctrine-queries-in-symfony2/ (some code examples)
I don't know your user story behind this, but I also heard that it is recommended to use one to many relationship instead of many to many, unless there is a strong reason to do so, as most of cases can be handled by one to many by reconsidering models.

load related entiites from doctrine collection symfony2

I have category table and make table. Both tables related by third category_make table creating many to many relationship.
/**
* #var \Doctrine\Common\Collections\Collection
*
* #ORM\ManyToMany(targetEntity="Ladisi\MotorsBundle\Entity\Make", inversedBy="catogory", fetch="EAGER")
* #ORM\JoinTable(name="catogory_make",
* joinColumns={
* #ORM\JoinColumn(name="catogory_id", referencedColumnName="cat_id")
* },
* inverseJoinColumns={
* #ORM\JoinColumn(name="make_id", referencedColumnName="make_id")
* }
* )
*/
private $make;
I want to get makes that belongs to particular category. I have tried,
$query = $em
->createQuery(
'SELECT c, m FROM LadisiMotorsBundle:Catagory c
JOIN c.make m
WHERE c.catId= :id'
)->setParameter('id', $id);
$result = $query->getResult();
but every time I get only category fields, make entity is not available in result. I also tried to get makes just by calling getMakes method on catagory object, it also returns null (not entity, i guess proxy). How do i solve this. Any help would be great.
You've already created a linking table, so the only thing you have to do (if you have your entities configured correctly) in your controller:
$catagory = $this->getDoctrine()->getManager()->getRepository('LadisiMotorsBundle:Catagory')->findOneBy(['id' => $id]);
$catagory->getMakes();

doctrine query builder join adding table twice

UPDATED at bottom:
I am trying to do what should be a simple join between two tables. I have a Gig table and a Venue table for a simple band site that I am building using Symfony2 (2.2). It's my first time with Symfony2 and doctrine so it is possible I am going completely in the wrong direction. I have created and populated the tables with DataFixtures and have verified that the ID relationships are correct. The problem I am getting is that the resulting DQL query has the Gig table referenced twice in the FROM section and that is causing me to get back several instances of the same record instead of the x number of records I am expecting. I don't know what I am doing wrong for that to be happening. Also, there may be an easier way of doing this but I am exploring all of my options since I am teaching myself Symfony2 in the process of building the site.
The Gig table contains a venue_id pointing to a Venue table that is defined in the Gig entity as a ManyToOne relationship (shown below). Using a doctrine findAll everything seems to work fine with the Venue class in the Gig Entity being populated correctly. I am trying to create a flat view of a few of the most recent Gigs to be displayed on the front page so I figured I would try to use a Join and include only the fields I need.
Here is the Repository Query:
public function getGigsWithLimit($maxGigs)
{
$qb = $this->createQueryBuilder('b')
->select('
g.gigDate,
g.startTime,
g.endTime,
g.message1 as gig_message1,
g.message2 as gig_message2,
g.url,
v.name,
v.address1,
v.address2,
v.city,
v.state,
v.zip,
v.phone,
v.url as venue_url,
v.message1 as venue_message1,
v.message2 as venue_message2,
v.message3 as venue_message3'
)
->from('WieldingBassBundle:Gig', 'g')
->leftJoin('g.venue', 'v')
->orderBy('g.gigDate', 'DESC')
->setMaxResults($maxGigs);
return $qb->getQuery()->getResult();
}
Here is the DQL it creates:
SELECT
g0_.id AS id0,
g0_.gig_date AS gig_date1,
g0_.start_time AS start_time2,
g0_.end_time AS end_time3,
g0_.message1 AS message14,
g0_.message2 AS message25,
g0_.url AS url6,
v1_.name AS name7,
v1_.address1 AS address18,
v1_.address2 AS address29,
v1_.city AS city10,
v1_.state AS state11,
v1_.zip AS zip12,
v1_.phone AS phone13,
v1_.url AS url14,
v1_.message1 AS message115,
v1_.message2 AS message216,
v1_.message3 AS message317
FROM
Gig g2_,
Gig g0_
LEFT JOIN
Venue v1_ ON g0_.venue_id = v1_.id
LIMIT
6
The Gig g2_ is my problem. If I delete it and execute the query everything is as expected. I don't know what is generating that.
The first table Gigs Entity looks like this (I am leaving out the getters and setters):
/**
* Gig
*
* #ORM\Table()
* #ORM\Entity(repositoryClass="Wielding\BassBundle\Entity\GigRepository")
* #ORM\HasLifecycleCallbacks
*/
class Gig
{
/**
* #var integer
*
* #ORM\Column(name="id", type="integer")
* #ORM\Id
* #ORM\GeneratedValue(strategy="AUTO")
*/
private $id;
/**
* #var \DateTime
*
* #ORM\Column(name="gig_date", type="date")
*/
private $gigDate;
/**
* #var \DateTime
*
* #ORM\Column(name="start_time", type="datetime")
*/
private $startTime;
/**
* #var \DateTime
*
* #ORM\Column(name="end_time", type="datetime")
*/
private $endTime;
/**
* #var string
*
* #ORM\Column(name="message1", type="string", length=50, nullable=true)
*/
private $message1;
/**
* #var string
*
* #ORM\Column(name="message2", type="string", length=50, nullable=true)
*/
private $message2;
/**
* #var string
*
* #ORM\Column(name="url", type="string", length=128, nullable=true)
*/
private $url;
/**
* #var integer
*
* #ORM\Column(name="venue_id", type="integer")
*/
private $venueId;
/**
* #ORM\Column(type="datetime")
*/
protected $created;
/**
* #ORM\Column(type="datetime")
*/
protected $updated;
/**
* #ORM\ManyToOne(targetEntity="Venue", cascade="persist")
* #ORM\JoinColumn(name="venue_id", referencedColumnName="id")
*/
protected $venue;
The Venue table is simple and does not have any relationships defined so I will leave it out unless it is asked for.
Any ideas? Thanks for any help.
Andrew
I removed everything except what would recreate the problem and here is what I was left with:
I simplified the repository method to:
public function getGigsWithLimit2($maxGigs)
{
$qb = $this->createQueryBuilder('a')
->select('g.id')
->from('WieldingBassBundle:Gig', 'g')
->setMaxResults($maxGigs);
return $qb->getQuery()->getResult();
}
This now generates:
SELECT
g0_.id AS id0
FROM
Gig g1_,
Gig g0_
LIMIT
6
There is that darn Gig g1_ problem again. I got the "Explain Query" from the Symfony profiler and it shows:
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE g1_ index IDX_ED7D664240A73EBA 4 9 Using index
1 SIMPLE g0_ index IDX_ED7D664240A73EBA 4 9 Using index; Using join buffer
I don't pretend to know what that means but it shows both table entries with different information about how it was used.
whats the use of "venueId" if you already got "venue" which contains the foreign key?
I found the problem. I am not used to Doctrine and was using the ->from in a repository that did not need it since the entity was automatically related through the annotations. My earlier query that worked was in the controller and not a repository so the ->from was necessary.
You are trying to do SQL. Doctrine is different. Your query fetches every field. Doctrine prefers to fetch entities. I think you probably want this:
public function getGigsWithLimit($maxGigs)
{
$qb = $this->createQueryBuilder('g')
->leftJoin('g.venue', 'v')
->orderBy('g.gigDate', 'DESC')
->setMaxResults($maxGigs);
return $qb->getQuery()->getResult();
}
The return result is a list of entities which you can call all the specific methods directly. You are still welcome to specify fields with doctrine, if you want partial objects, but I've found the normal method of fetching the entire entity covers most of my needs.
This is a fundamentally different paradigm than SQL and will take some getting used to.

Select many to many entity collection using DQL

I have to entities that have ManyToMany relation with linking table. Like this:
class User
{
/**
* #ORM\ManyToMany(targetEntity="Post")
* #ORM\JoinTable(name="favorite_posts",
* joinColumns={#ORM\JoinColumn(name="user_id", referencedColumnName="id")},
* inverseJoinColumns={#ORM\JoinColumn(name="post_id", referencedColumnName="id")}
* )
**/
private $favoritePosts;
}
class Post
{
/**
* #ORM\ManyToMany(targetEntity="User", mappedBy="favoritePosts")
*/
private $usersInFavorite;
}
And I can get all user's favorite posts using a User entity object:
$favorites = $user->getFavoritesPosts();
But I have no idea how to get EXACTLY THE SAME result using DQL or Doctrine Query Builder. Under result i mean an array of POST entity objects.
Based on this exemple
If you want to fetch it by dql,
$dql = "SELECT p FROM Posts p INNER JOIN p.$usersInFavorite u WHERE u= ?1";
$query = $entityManager->createQuery($dql)
->setParameter(1, $user);
$favoritePosts = $query->getResult();
I tested it this time and i found the results as requested.
if you have the id of the user entity instead of the entity the same code will work with $user being the id of the user.

NULL inserted while Persisting new Entity, Mapping table column to 2 tables. doctrine 2

I need to map the same column to 2 differences tables (lets say normal and extended).
/**
* #var ItemValue
*
* #OneToOne(targetEntity="ItemValue")
* #JoinColumn(name="id_value", referencedColumnName="id_value")
*/
private $value;
/**
* #var ItemValueExtended
*
* #OneToOne(targetEntity="ItemValueExtended")
* #JoinColumn(name="id_value", referencedColumnName="id_value")
*/
private $valueExtended;
/**
* #var string $isExtended
*
* #Column(name="is_extended", type="string", nullable=false)
*/
private $isExtended = 'YES';
I have no problem with joining data based on the isExtended attribute using DQL:
"SELECT id,idv FROM ItemData id
JOIN id.value idv WHERE id.isExtended='NO'";
and
"SELECT id,idv FROM ItemData id
JOIN id.valueExtended idv WHERE id.isExtended='YES'";
but when ever I want to persist a new object, NULL is inserted in id_value column ?!!
$oValue = ItemValue();
.
.
$oData = new ItemData();
$oData->setValue($oValue);
.
.
.
$em->persist($oData);
$em->flush();
Any Idea ?
From Doctrine2 documentation:
In the case of bi-directional associations you have to update the
fields on both sides.
One possible solution would be:
$oData = new ItemData();
$oData->setValue($oValue);
$oValue->setData($oData);
but it's tedious. Another better one is set the cascade option on both sides of the one-to-one association:
#OneToOne(targetEntity="ItemValue"), cascade={"persist", "remove"})
This way your code will work. You can choose the appropriate cascade options looking at here.
In the case where both the parent and child entity are new entities (neither have been persisted) a PrePersist lifecycle event on the parent can help:
/**
* ....
*
* #ORM\HasLifecycleCallbacks
*/
class ParentEntity {...
/**
* #ORM\PrePersist()
*/
public function prePersist() {
foreach($this->getChildEntities() as $childEntity) {
$childEntity->setParent($this);
}
}
-
class ChildEntity {
....
This will automatically create the child -> parent relationship upon saving the parent.
In many instances Doctrine will then be able to work out the rest at the SQL level.

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