I have two tables, User
and Post
. One User
can have many posts
and one post
belongs to only one user
.
In my User
model I have a hasMany
relation...
public function post(){
return $this->hasmany('post');
}
And in my post
model I have a belongsTo
relation...
public function user(){
return $this->belongsTo('user');
}
Now I want to join these two tables using Eloquent with()
but want specific columns from the second table. I know I can use the Query Builder but I don't want to.
When in the Post
model I write...
public function getAllPosts() {
return Post::with('user')->get();
}
It runs the following queries...
select * from `posts`
select * from `users` where `users`.`id` in (<1>, <2>)
But what I want is...
select * from `posts`
select id,username from `users` where `users`.`id` in (<1>, <2>)
When I use...
Post::with('user')->get(array('columns'....));
It only returns the column from the first table. I want specific columns using with()
from the second table. How can I do that?
This question is related to
php
laravel
orm
eloquent
laravel-query-builder
If you use PHP 7.4 or later you can also do it using arrow function so it looks cleaner:
Post::with(['user' => fn ($query) => $query->select('id','username')])->get();
public function getSection(Request $request)
{
Section::with(['sectionType' => function($q) {
$q->select('id', 'name');
}])->where('position',1)->orderBy('serial_no', 'asc')->get(['id','name','','description']);
return response()->json($getSection);
}
Model code
public function sectionType(){
return $this->belongsTo(Section_Type::class, 'type_id');
}
In Laravel 5.7 you can call specific field like this
$users = App\Book::with('author:id,name')->get();
It is important to add foreign_key
field in the selection.
EmployeeGatePassStatus::with('user:id,name')->get();
When going the other way (hasMany):
User::with(array('post'=>function($query){
$query->select('id','user_id');
}))->get();
Don't forget to include the foreign key (assuming it is user_id in this example) to resolve the relationship, otherwise you'll get zero results for your relation.
For loading models with specific column, though not eager loading, you could:
In your Post
model
public function user()
{
return $this->belongsTo('User')->select(array('id', 'username'));
}
Original credit goes to Laravel Eager Loading - Load only specific columns
Now you can use the pluck
method on a Collection
instance:
This will return only the uuid
attribute of the Post model
App\Models\User::find(2)->posts->pluck('uuid')
=> Illuminate\Support\Collection {#983
all: [
"1",
"2",
"3",
],
}
In your Post
model:
public function userWithName()
{
return $this->belongsTo('User')->select(array('id', 'first_name', 'last_name'));
}
Now you can use $post->userWithName
If you want to get specific columns using with()
in laravel eloquent then you can use code as below which is originally answered by @Adam in his answer here in response of this same question :
Post::with('user:id,username')->get();
So i have used it in my code but it was giving me error of 1052: Column 'id' in field list is ambiguous
, so if you guys are also facing same problem
Then for solving it you have to specify table name before the id column in with()
method as below code:
Post::with('user:user.id,username')->get();
Note that if you only need one column from the table then using 'lists' is quite nice. In my case i am retrieving a user's favourite articles but i only want the article id's:
$favourites = $user->favourites->lists('id');
Returns an array of ids, eg:
Array
(
[0] => 3
[1] => 7
[2] => 8
)
You can do it like this since Laravel 5.5:
Post::with('user:id,username')->get();
Care for the id
field and foreign keys
as stated in the docs:
When using this feature, you should always include the id column and any relevant foreign key columns in the list of columns you wish to retrieve.
For example, if the user belongs to a team and has a team_id
as a foreign key column, then $post->user->team
is empty if you don't specifiy team_id
Post::with('user:id,username,team_id')->get();
Try with conditions.
$id = 1;
Post::with(array('user'=>function($query) use ($id){
$query->where('id','=',$id);
$query->select('id','username');
}))->get();
I came across this issue but with a second layer of related objects. @Awais Qarni's answer holds up with the inclusion of the appropriate foreign key in the nested select statement. Just as an id is required in the first nested select statement to reference the related model, the foreign key is required to reference the second degree of related models; in this example the Company model.
Post::with(['user' => function ($query) {
$query->select('id','company_id', 'username');
}, 'user.company' => function ($query) {
$query->select('id', 'name');
}])->get();
Additionally, if you want to select specific columns from the Post model you would need to include the user_id column in the select statement in order to reference it.
Post::with(['user' => function ($query) {
$query->select('id', 'username');
}])
->select('title', 'content', 'user_id')
->get();
So, similar to other solutions here is mine:
// For example you have this relation defined with "user()" method
public function user()
{
return $this->belongsTo('User');
}
// Just make another one defined with "user_frontend()" method
public function user_frontend()
{
return $this->belongsTo('User')->select(array('id', 'username'));
}
// Then use it later like this
$thing = new Thing();
$thing->with('user_frontend');
// This way, you get only id and username,
// and if you want all fields you can do this
$thing = new Thing();
$thing->with('user');
You can also specify columns on related model at the time of accessing it.
Post::first()->user()->get(['columns....']);
Source: Stackoverflow.com