Laravel transform not working as intended on collection - php

I have a collection which is an eloquent query.
There is one column where I want to replace the value with another value.
I am using the transform function to do this however it is not working as intended.
Here is my query in the controller :
$articles = KnowledgeBaseArticle::getArticlesByDepartment($department)
->get()
->transform(function ($article) {
$article->category_id = KnowledgeBaseCategory::find($article->category_id)->name;
});
And the getArticlesByDepartment query from the model:
public function scopeGetArticlesByDepartment($query, $department){
return $query->where('department', $department)
->select('title', 'updated_at', 'department', 'id', 'category_id')
->orderBy('title', 'asc');
}
I want to return it so that all the rows with column category_id is replaced with the category name. You can see I am trying to do this by using $article->category_id by using find on the KnowledgeBaseCategory model to retrieve this. However this is not working at all and when I die and dump, I get an single column array full of nulls.
When I have died and dumped $article->category_id & find query inside the transform, it is returning the correct category name, it is just not replacing the category_id column with the category name.
I have also tried map instead of transform and got the same result.
If it matters, I am later on converting this data into JSON.
Where am I going wrong?

Transform, not unlike map, needs you to return the modified item of the collection, as this will replace the existing item.
transform(function ($article) {
$article->category_id = KnowledgeBaseCategory::find($article->category_id)->name;
return $article;
});
Since objects are mutable and passed by reference, you can just do this in an each() closure instead to save a line:
each(function ($article) {
$article->category_id = KnowledgeBaseCategory::find($article->category_id)->name;
});
Though, you really should have a relationship set up for category. There's no reason to be performing this find logic in your controller.

Related

How to select only one Column with scope of eloquent model?

I got two tables. Both have a relationship to each other. I´m trying to query both to get the matching results. This results get checked if they also have an column which matches with a parameter value.
I´m trying it with a scope and it work. I only need one column from the second table and I´m trying to use it as column in my first table when I got my result.
So the code works and I got an result but I´m trying to filter to select only one column from the second table.
My code look like that.
My controller:
public function test()
{
$UID='LQuupgYvnuVzbEoguY4TF8bnHUU2';
$event=Events::withState($UID)->get();
echo $event;
}
My model scope function:
public function scopeWithState($query,$UID){
return $query->with(['EventLiked' => function($query) use($UID) {
$query
->where('EventLiked.UID', $UID)
;
}]);
}
My hasMany relationship function:
public function EventLiked()
{
return $this->hasMany(EventLiked::class,'EID','ID')->select('State','UID','EID');
}
I would go for specifying columns inside closure.
New scope:
public function scopeWithState($query,$UID){
return $query->with(['EventLiked' => function($query) use($UID) {
$query
->where('EventLiked.UID', $UID)
->select('State');
}]);
}
Calling scope:
$event=Events::withState($UID)->get();
You're not getting expected results because Laravel splits it into 2 queries:
First, for selecting events.
Then it plucks EID
Second, when it looks for EventLiked where matching ID's is found (from second step) and loads as relationships.
So you want to change select statement only in 2nd query. Not in a first one

Get comment sub-comments when only one sub-comment

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.

Laravel fetch data from model where the condtions is from another model

I have a table called List which i planned to be displayed into view with this command : $lists= List::with('user', 'product.photodb', 'tagCloud.tagDetail')->get();. But, i want the data displayed is only those that has TagID equal to the one user inputted. Those data can be retrieved from TagCloud table.
What i am currently doing is :
$clouds = TagCloud::select('contentID')
->where('tagDetailID', '=', $tagID)
->get();
$lists = List::with('user', 'product.photodb', 'tagCloud.tagDetail')
->where('id', '=', $clouds->contentID)
->get();
But when i tried to run it, it only return a null value, even though when i am doing return $clouds, it does returned the desired ID.
Where did i do wrong ? Any help is appreciated !
A couple of gotchas with your current solution.
Using get() returns an Illuminate\Database\Eloquent\Collection object. Hence you can't use $clouds->contentID directly since $clouds is a collection (or array if you prefer). See Collection Documentation.
where(...) expects the third parameter to be a string or integer, aka single value. Instead, you are passing a collection, which won't work.
The correct way is to use whereHas() which allows you to filter through an eager loaded relationship.
Final Code:
$lists = List::with('user', 'product.photodb', 'tagCloud.tagDetail')
->whereHas('tagCloud',function($query) use ($tagID) {
return $query->where('contentID','=',$tagID);
})
->get();
See WhereHas Documentation.
What you want is whereHas()
$list = List::with(...)
->whereHas('relation', function($q) use($id) {
return $q->where('id', $id);
})->get();
Apply Where condition in you tagCloud model method tagDetail
public function tagDetail(){
return $q->where('id', $id);
}

Pull out the specific data when the relation ship is many to many in laravel

I want to ask about how to pull out the specific data (some columns) from the Laravel database
Here is my code :
User Model :
public function events(){
return $this->belongsToMany('App\Events')->withTimestamps();
}
Event Controller :
public function showjson(){
$user_id=Auth::user()->id;
$events = DB::table('events')
->select(
'id',
'calendar_title as title',
'startdate as start',
'enddate as end',
'calendar_color as backgroundColor',
'calendar_color as borderColor')
->where('user_id',$user_id)
->get();
$user=Auth::user();
$eventData=$user->events;
return $eventData;
}
I have already the relationship between this two, I can get the data through this :
$user = Auth::user();
$eventData = $user->events;
But I want to get specific columns by name, like in select code above.
Would that be another way that I can call the specific data and change the column name?
i want display in json only the calendar_title, calendar_des only.
You can use lists to retrieve a list of column values, take a look at Database Query Builder Retrieving Results section :
$user->events->lists('calendar_title','calendar_des');
If you want to return Json format you can use toJson() method :
$user->events->lists('calendar_title','calendar_des')->toJson();
Hope this helps.

Laravel - Unnecessary columns still being loaded with select statement

I am wanting to limit a controller's function's result to only pass certain columns into the view.
It is necessary because it will be used within an API, and so I need the results to be as streamlined as possible.
I have done this successfully with the following function:
public function getIndex()
{
$alerts = Criteria::select('id', 'user_id', 'coordinate_id', 'alert_name')
->with(['coordinate' => function($q){
$q->select('name', 'id');
}])
->get();
}
So it only returns id, user_id and coordinate_id from the criteria table.
However on the function below, I am using a has query (to access a relationship), and thus, using with afterwards to limit the columns, but it's still returning all:
public function getMatches()
{
$matches = Criteria::select('id')
->has('alerts')
->with(['alerts' => function ($q){
$q->select('id', 'headline', 'price_value', 'price_type');
}])
->with('alerts.user.companies')
->get();
}
But, for example, it's still returning the description column, which is in the alert's table. The with query proceeding the has query clearly isn't working (but it's presenting no errors).
Also, the ->with('alerts.user.companies') query, is returning everything within the user's table, which is also unnecessary. How can I return just the companies table data, that's related to the user, who's related to the alert?
Your help would be greatly appreciated.
Depending what you want to achieve, you could use $hidden property to hide columns you don't want to return as json or arrays.
In your Alert model you could do:
protected $hidden = ['description'];
And this way description field won't be returned.
If it's not the way for you (sometimes you want to return description) you could create extra relationships where you limit fields from database.
You could for example create the following relationship:
public function alertsSimple() {
return $this->hasMany('Alert')->select('id', 'headline', 'price_value', 'price_type', 'criteria_id');
}
Also maybe in your select the problem is that you don't use foreign key at all. You could also try with:
$q->select('id', 'headline', 'price_value', 'price_type','criteria_id');
instead of
$q->select('id', 'headline', 'price_value', 'price_type');

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