I have got three tables in laravel like so:
Users, posts, and comments
I'm trying to come up with a query that fetches me all the user's posts, plus the date of last comment with each post.
Approach i've taken that's not working perfectly is:
$posts = User::find($userId)->posts()->with('latestComment')->get();
In my Post model I have:
public function latestComment()
{
return $this->hasOne(Comment::class)->latest();
}
In my findings, i haven't been to see a way to get the date from the lastComment load.
Any pointers welcome,
Thanks
Just discovered one needs to add the foreign key to the select method like so:
return $this->hasOne(Comment::class)->latest()->select('field','foreign_key');
You should use eager loading constraint. Code from the other answers will first load all comments, which you don't want.
$posts = Post::where('user_id', $userId)
->with(['comments' => function($q) {
$q->taletst()->take(1);
}])
->get();
You can use the existing relationship and get the latest comment.
public function comments() {
return $this->hasMany(Comment::class);
}
public function latestComment() {
return $this->comments()->last();
}
Related
I have comments table where has parent_id
This is Comment table sub_comments relation.
public function sub_comments()
{
return $this->hasMany(self::class, 'parent_id');
}
This code return all comments with related all sub-comments
Comment::with('sub_comments')->get();
But I want to get all comments also sub-comments when sub-comments is single. That mean if comment have 2 or more comments for that comment I did not want get that sub-comments.
Now I use this code
$oneSubcommentCommentIds = Comment::has('sub_comments', '=', 1)->pluck('id');
Comment::with([
'sub_comments' => function ($q) use ($oneSubcommentCommentIds) {
$q->whereIn('parent_id', $oneSubcommentCommentIds);
}
])->get();
but this make one additional query.
Try this:
Comment::with('sub_comments')->has('sub_comments', '=', 1)->get();
Update
Your question wasn't clear, I can't imagine another way to doing this without previosly loaded the relationship or the count of the relationship.. so I'd do this:
// First get all your comments with an aditional count field
$comments = Comments::withCount('sub_comments')->get();
// separate the ones with just one sub_comment from the rest
list($oneSubComment, $theRest) = $collection->partition(function ($comment) {
return $comment->sub_comments_count == 1;
});
// Then load the relationship on just the selected elements
$oneSubComment->load('sub_comments');
// re-join the collection
$comments = $oneSubComment->union($theRest);
What am I doing here?
Adding an additional field to each $comment with the relationship count (it should be something like sub_comments_count)
Partition the resulting collection in two parts: the ones with one comment and the rest. Using the partition() method.
Lazy eager loading the collection.
Re-joining the two collections using the union() method.
sorry for the title of this question but I am not sure how to ask it...
I am working on a project where I have two Models Trains and Cars, to this model I have a belonging Route.
I want to make a query and check if the routeable_type is App\Car than with the selected routeable_id to get the data from the Car. And if the routeable_type is Train then with the ID to get the data from the Tran.
So my models go like this:
Train:
class Train extends Model
{
public function routes()
{
return $this->morphMany('App\Route', 'routeable');
}
}
Car:
class Car extends Model
{
public function routes()
{
return $this->morphMany('App\Route', 'routeable');
}
}
Route:
class Route extends Model
{
public function routeable()
{
return $this->morphTo();
}
}
And the query I have at the moment is:
$data = Route::leftjoin('cars', 'cars.id', '=', 'routes.routeable_id')
->leftjoin('trains', 'trains.id', '=', 'routes.routeable_id')
->select('routes.id', 'cars.model AS carmodel', 'trains.model AS trainmodel', 'routeable_type', 'routes.created_at');
With this query if I have the same ID in cars and trains I get the data from both and all messes up. How do I check if routeable_type is Car ... do this, if routeable_type is Train .. do that?
Will something like this be possible in a 1 single query:
$data = Route::select('routes.id', 'routeable_type', 'routes.created_at');
if(routeable_type == 'Car'){
$data = $data->leftjoin('cars', 'cars.id', '=', 'routes.routeable_id')->select('routes.id', 'cars.model AS carmodel', 'routeable_type', 'routes.created_at');
}else{
$data = $data->leftjoin('trains', 'trains.id', '=', 'routes.routeable_id')->select('routes.id', 'trains.model AS trainmodel', 'routeable_type', 'routes.created_at');
}
Maybe this is what you are looking for?
DB::table('routes')
->leftJoin('cars', function ($join) {
$join->on('cars.id', '=', 'routes.routeable_id')
->where('routes.routeable_type', 'App\Car');
})
->leftJoin('trains', function ($join) {
$join->on('trains.id', '=', 'routes.routeable_id')
->where('routes.routeable_type', 'App\Train');
})
->select('routes.id', 'cars.model AS car_model', 'trains.model AS train_model', 'routes.routeable_type', 'routes.created_at');
->get();
I think you may want to follow the morphedByMany design.
https://laravel.com/docs/5.7/eloquent-relationships#many-to-many-polymorphic-relations
This was also a neat visual for the different relation types.
https://hackernoon.com/eloquent-relationships-cheat-sheet-5155498c209
I was faced with a similar issue though I failed to follow the correct design initially and was forced to query the many possible relations then wrote custom logic after to collect the relation types and ids then do another query and assign them back through iteration. It was ugly but worked... very similar to how Eloquent does things normally.
i don't have enough repo, so i can't comment. that's why i am putting as an answer.
You should use 2 different queries, for each model.
This will be better, code wise as well as performance wise. also if both models have similar fields you should merge them to 1 table and add a 'type' column.
and put non-similar fields in a 'meta' column.
( in my opinion )
I need to OrderBy a column with collection.
I need to orderBy(updated_at, 'desc') all posts which owned by current logged user.
Here is my code :
$posts = auth()->user()->posts->sortByDesc('updated_at');
Here is User model :
class User extends Authenticatable
{
public function posts()
{
return $this->hasMany(Post::class);
}
}
It doesn't return any errors also doesn't sort !
Any helps would be great appreciated.
P.S:
I know I can achieve this with :
$posts = Post::where('user_id', auth()->user()->id)->orderBy('updated_at', 'desc')->get();
But I would like to do the same thing with collections.
So this is how you sort with SQL:
$posts = auth()->user()->posts()->orderBy('updated_at', 'DESC');
And with collections:
$posts = auth()->user()->posts->sortByDesc('updated_at');
I've tested the 2nd one and it works as intended for me.
Documentation: https://laravel.com/docs/6.x/collections#method-sortbydesc
*Its available since Laravel 5.1
#devk is right. What I wrote in the first post is correct.
The problem was in DataTables in the the view.
It needed to add this line to the Datatables options:
"order": [[ 5, 'desc' ]], // 5 is the `updated_at` column (the sixth column in my case)
So this is working fine :
$posts = auth()->user()->posts->sortByDesc('updated_at');
Try adding the following to your User model
public function posts_sortedByDesc(){
return $this->hasMany(Post::class)->sortByDesc('updated_at');
}
Then get the posts by calling posts_sortedByDesc instead of posts
I have 3 models
User
Channel
Reply
model relations
user have belongsToMany('App\Channel');
channel have hasMany('App\Reply', 'channel_id', 'id')->oldest();
let's say i have 2 channels
- channel-1
- channel-2
channel-2 has latest replies than channel-1
now, i want to order the user's channel by its channel's current reply.
just like some chat application.
how can i order the user's channel just like this?
channel-2
channel-1
i already tried some codes. but nothing happen
// User Model
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved')
->with(['replies'])
->orderBy('replies.created_at'); // error
}
// also
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved')
->with(['replies' => function($qry) {
$qry->latest();
}]);
}
// but i did not get the expected result
EDIT
also, i tried this. yes i did get the expected result but it would not load all channel if there's no reply.
public function channels()
{
return $this->belongsToMany('App\Channel')
->withPivot('is_approved')
->join('replies', 'replies.channel_id', '=', 'channels.id')
->groupBy('replies.channel_id')
->orderBy('replies.created_at', 'ASC');
}
EDIT:
According to my knowledge, eager load with method run 2nd query. That's why you can't achieve what you want with eager loading with method.
I think use join method in combination with relationship method is the solution. The following solution is fully tested and work well.
// In User Model
public function channels()
{
return $this->belongsToMany('App\Channel', 'channel_user')
->withPivot('is_approved');
}
public function sortedChannels($orderBy)
{
return $this->channels()
->join('replies', 'replies.channel_id', '=', 'channel.id')
->orderBy('replies.created_at', $orderBy)
->get();
}
Then you can call $user->sortedChannels('desc') to get the list of channels order by replies created_at attribute.
For condition like channels (which may or may not have replies), just use leftJoin method.
public function sortedChannels($orderBy)
{
return $this->channels()
->leftJoin('replies', 'channel.id', '=', 'replies.channel_id')
->orderBy('replies.created_at', $orderBy)
->get();
}
Edit:
If you want to add groupBy method to the query, you have to pay special attention to your orderBy clause. Because in Sql nature, Group By clause run first before Order By clause. See detail this problem at this stackoverflow question.
So if you add groupBy method, you have to use orderByRaw method and should be implemented like the following.
return $this->channels()
->leftJoin('replies', 'channels.id', '=', 'replies.channel_id')
->groupBy(['channels.id'])
->orderByRaw('max(replies.created_at) desc')
->get();
Inside your channel class you need to create this hasOne relation (you channel hasMany replies, but it hasOne latest reply):
public function latestReply()
{
return $this->hasOne(\App\Reply)->latest();
}
You can now get all channels ordered by latest reply like this:
Channel::with('latestReply')->get()->sortByDesc('latestReply.created_at');
To get all channels from the user ordered by latest reply you would need that method:
public function getChannelsOrderdByLatestReply()
{
return $this->channels()->with('latestReply')->get()->sortByDesc('latestReply.created_at');
}
where channels() is given by:
public function channels()
{
return $this->belongsToMany('App\Channel');
}
Firstly, you don't have to specify the name of the pivot table if you follow Laravel's naming convention so your code looks a bit cleaner:
public function channels()
{
return $this->belongsToMany('App\Channel') ...
Secondly, you'd have to call join explicitly to achieve the result in one query:
public function channels()
{
return $this->belongsToMany(Channel::class) // a bit more clean
->withPivot('is_approved')
->leftJoin('replies', 'replies.channel_id', '=', 'channels.id') // channels.id
->groupBy('replies.channel_id')
->orderBy('replies.created_at', 'desc');
}
If you have a hasOne() relationship, you can sort all the records by doing:
$results = Channel::with('reply')
->join('replies', 'channels.replay_id', '=', 'replies.id')
->orderBy('replies.created_at', 'desc')
->paginate(10);
This sorts all the channels records by the newest replies (assuming you have only one reply per channel.) This is not your case, but someone may be looking for something like this (as I was.)
I have two models. i.e, Posts and Tags.
Post Model
public function tags()
{
return $this->belongsToMany('App\Models\Tag', 'tbl_post_tags', 'in_post_id', 'in_tag_id');
}
Tag Model
public function posts()
{
return $this->belongsToMany('App\Models\Post', 'tbl_post_tags', 'in_tag_id', 'in_post_id');
}
I want to fetch those posts which have php tag.
This is what I have done till now.
Search Controller
Post::with(['tags'])->skip(0)->take(5)->get();
I'm getting first five posts from table. But there is a post in these list which doesn't have PHP tag. So as per my requirement, I must get next post from table which have PHP tag.
I can't find any document on official site of laravel. If anyone knows the answer, it will be appreciated.
Assuming that you search the tags by name, here is the code.
Post::with(['tags'])->whereHas('tags', function($query){
$query->where("name", 'PHP');
})->skip(0)->take(5)->get();
Post::whereHas(['tags' => function($q) use($name){
$q->where('name', $name); // $name = 'PHP'
}])->take(5)->get();