laravel relation code example
Example 1: laravel where on relation
Event::whereHas('participants', function ($query) {
$query->where('IDUser', '=', 1);
})->get();
Example 2: laravel where has
use Illuminate\Database\Eloquent\Builder;
// Retrieve posts with at least one comment containing words like foo%...
$posts = App\Post::whereHas('comments', function (Builder $query) {
$query->where('content', 'like', 'foo%');
})->get();
// Retrieve posts with at least ten comments containing words like foo%...
$posts = App\Post::whereHas('comments', function (Builder $query) {
$query->where('content', 'like', 'foo%');
}, '>=', 10)->get();
Example 3: laravel relation of relation
//Multiple relationships:
$books = Book::with('author', 'publisher')->get();
//Nested relationships:
$books = Book::with('author.contacts')->get();
Example 4: how to use where relationship laravel
Event::with(["owner", "participants" => function($q) use($someId){
$q->where('participants.IdUser', '=', 1);
//$q->where('some other field', $someId);
}])
Example 5: where query from relation table in laravel
UserModel::whereHas('attachments', function ($attachmentQuery) {
$attachmentQuery->where('level', 'profile_level');
})->get();
If you want from already queried model get specific attachments then write
$userModel->attachments()->where('level', 'profile_level')->get();
it is impossible to query both UserModel and AttachementModel in single query,
it must be at least two queries. Even fancy
UserModel::with('attachments')->get();,
which returns user with all attachments, do internally two queries.
OR:
I noticed that you can define relation constraints within with method
UserModel::with(['attachments' => function ($attachmentQuery) {
$attachmentQuery->where('level', 'profile_level');
}])->get();
Example 6: one to many laravel
For example, a blog post may have an infinite number of comments. And a single
comment belongs to only a single post
class Post extends Model
{
public function comments()
{
return $this->hasMany('App\Models\Comment');
}
}
class Comment extends Model
{
public function post()
{
return $this->belongsTo('App\Models\Post');
}
}