My database structure is the following:
So I've got a Bloggers table (sorry for the typo in the image), which has 3 topic fields, all 3 are foreign keys to the topics' table id.
I made a Blogger view front-end with a simple table showing all blogger columns. At the moment, the id's of the topics are being shown instead of the names though.
How can I change this?
I've already tried the following in my Controller, but that just creates duplicates in the view with different values in the main_topic column.
$bloggers= DB::table('bloggers')
->join('topics', function ($join) {
$join
->on('bloggers.main_topic', '=', 'topics.id')
->orOn('bloggers.subtopic1', '=', 'topics.id')
->orOn('bloggers.subtopic2', '=', 'topics.id');
})
->select('bloggers.*', 'topics.name as main_topic')
->get();
return view('pages.bloggers', compact('bloggers'));
The answer to my specific question was a little different from the answers given, so I'll post it here in case anyone needs it in the future.
So I've got 3 tables: bloggers, topics and a pivot table called blogger_topic. bloggers contains 3 foreign keys (integers) to topics called main_topic, subtopic1, subtopic2. The pivot table contains a blogger_id, and a topic_id.
What I ended up with:
Blogger.php model:
public function mainTopic()
{
return $this->belongsTo('App\Models\Topic', 'main_topic', 'id');
}
public function subtopicOne()
{
return $this->belongsTo('App\Models\Topic', 'subtopic1', 'id');
}
public function subtopicTwo()
{
return $this->belongsTo('App\Models\Topic', 'subtopic2', 'id');
}
Topic.php model:
public function bloggers()
{
return $this->belongsToMany('App\Models\Blogger');
}
View (blogger.blade.php):
#foreach($bloggers as $blogger)
{{ $blogger->mainTopic }}
{{ $blogger->subtopicOne }}
{{ $blogger->subtopicTwo }}
#endforeach
I think you should change your database tables if possible as below (sample link), by creating a pivot table. And then I think you should make relationships in Blogger and Topic model files with many-to-many. Then it would be very easy to fetch all related topics. For eg,
$topics = $blogger->topics;
Here you can reference the sample db table designs
I kindly recommend you to use models in Laravel coz they'll make your life more simple. Hope this help.
If you cant change your database, you could use group_concat on the results. Not sure if it will work but something like:
DB::table('bloggers')
->join('topics', function ($join) {
$join
->on('bloggers.main_topic', '=', 'topics.id')
->orOn('bloggers.subtopic1', '=', 'topics.id')
->orOn('bloggers.subtopic2', '=', 'topics.id');
})
->groupby('bloggers.id')
->select('bloggers.*', 'topics.name as main_topic', DB::raw('group_concat(topics.name)'))
->get();
Related
I have 4 table categories, initiatives, a pivot table for the "Many To Many" relationship category_initiative and initiativegroup table related with initiatives table with initiatives.initiativesgroup_id with one to many relation.
With pure sql I retrive the information I need with:
SELECT categories.id, categories.description, initiatives.id, initiatives.description, initiativegroups.group
FROM categories
LEFT JOIN category_initiative ON categories.id = category_initiative.category_id
LEFT JOIN initiatives ON category_initiative.initiative_id = initiatives.id
LEFT JOIN initiativegroups ON initiatives.initiativegroup_id = initiativegroups.id
WHERE categories.id = '40'
How can I use eloquent model to achieve same results?
Since you have such a specific query touching multiple tables, one possibility is to use query builder. That would preserve the precision of the query, retrieving only the data you specifically need. That would look something like this:
$categories = DB::table('categories')
->select([
'categories.id',
'categories.description',
'initiatives.id',
'initiatives.description',
'initiativegroups.group',
])
->leftJoin('category_initiative', 'categories.id', '=', 'category_initiative.category_id')
->leftJoin('initiatives', 'category_initiative.initiative_id', '=', 'initiatives.id')
->leftJoin('initiativegroups', 'initiatives.initiativegroup_id', '=', 'initiativegroups.id')
->where('categories.id', '=', 40)
->get();
In your models define the relationships:
Category.php model
public function initiatives()
{
return $this->belongsToMany('App\Initiative');
}
Initiative.php model (If has many categories change to belongs to many)
public function category()
{
return $this->belongsTo('App\Category');
}
Then maybe change your initiativegroup -> groups table, and then create a pivot table called group_initiative. Create model for group. Group.php and define the relationship:
public function initiatives()
{
return $this->belongsToMany('App\Initiative');
}
Then you can also add the following relationship definition to the Initiative.php model
public function group()
{
return $this->belongsTo('App\Group');
}
That should get you started.
for the record..
with my original relationship, but changing table name as alex suggest, in my controller:
$inits = Category::with('initiative.group')->find($id_cat);
simple and clean
I'm having a really strange issue with my eloquent query. I have a table called Calls which I am joining to Contacts and Companies. I am trying to reference the column calls.id but it has been replaced with the id for Companies.
Here is my query:
$calls=DB::table('calls')
->leftJoin('contacts','calls.contact_id','=','contacts.id')
->leftJoin('companies','calls.company_id','=','companies.id')
->where('completed','=',false)
->orderBy('call_on','asc')
->get();
return $calls;
I have seen on Github that this seems to be a known bug but no-one has put forward a workaround.
Can anyone point me in the right direction?
The most direction solution to your immediate question is to add a select to your Eloquent query:
$calls=DB::select('calls.* from calls')
->leftJoin('contacts','calls.contact_id','=','contacts.id')
->leftJoin('companies','calls.company_id','=','companies.id')
->where('completed','=',false)
->orderBy('call_on','asc')
->get();
return $calls;
Instead of the default select *, explicitly dictate what is returned. However, this can be done a lot more cleanly with Eloquent using models:
Calls::whereHas('companies', function (Builder $query) {
$query->where('completed', false);
})->orderBy('call_on', 'asc')->get();
In order for this to work you need to setup the relationship on the model level:
// App\Calls model:
public function companies() {
return $this->belongsTo(App\Companies::class);
}
// App\Companies model:
public function calls() {
return $this->hasMany(App\Calls::class);
}
I have two tables, products and product_images, now I want to show product which has at least one image.
In controller I have a simple function in ProductController to fetch all the products:
public function products(){
$allProducts = $this->product->paginate(15);
return view('frontend.pages.products',compact('allProducts'));
}
But, I want to send the products which has at least one image of each product.
What should I do to achieve that?
Edit:
I have created relationship between tables, now how can I get my desired answer?
I have written this in the Controller:
$allProducts = $this->product->whereHas('product_images', function ($query){
$query->where();
})->get();
Assuming table schema
product
-id
-name
product_image
-id
-product_id
-url //any columns you needed
$product_ids = DB::table('product')
->join('product_image','product_image.product_id','=','product.id')
->select('product.id','roduct.name')
->groupBy('product.id')
->get();
$product_count = count($product_ids);
Eloquent has this built in.
Example
// Retrieve all posts that have three or more comments...
$posts = App\Post::has('comments', '>=', 3)->get();
In your case
In your case you could change the $allProducts line to be
$allProducts = $this->product()->has('product_image', '>=', 1)->paginate(15);
I didn't test the code above.
See documentation for more information on this topic.
https://laravel.com/docs/6.x/eloquent-relationships#querying-relationship-existence
You can use selectRaw:
$products = Product::leftJoin('product_images',function ($join){
$join->on('products.product_id','=','product_images.product_id');
})->selectRaw("products.product_id i, count(product_images.id) c")
->groupBy('products.product_id')
->where('c','>=',3)
->get();
Getting answer querying realtionship:
The query will look like following:
$allProducts = $this->product->has('Images')->paginate(15);
But, make you sure you have created relation in Model like the following:
public function Images(){
return $this->hasMany('\App\Models\ProductImages');
}
I have used hasMany relationship because one product can have multiple images.
I am using laravel 5.6. I've two tables. One is Teachers(id,name,email,salary) another is Students(id,teacher_id,name,email) I have joined 2 tables
$vu_data = Teacher::join('Students', 'teachers.id', '=', 'students.teacher_id')
->where('teachers.id', $id)
->get();
return view('view_full')->with('vu_data',$vu_data);
view_full.blade.php
{{$vu_data[0]->name}}
How can I display sthdent name and teacher nam. There are same column name.
Thanks in advance
The better way is to use laravel Eloquent relationships https://laravel.com/docs/5.7/eloquent-relationships#one-to-many*.
Put on your Teachers model
public function students(){
return $this->hasMany('App\Students', 'teacher_id', 'id');
}
You will call like that:
$vu_data->students()
If you want to use yur select, simple use de 'AS'
->select('Teachers.name as teacher_name', 'Students.name as student_name')
You'll need to specify the columns in a select() clause on the query, and rename the columns. Such as
Teacher::join('Students', 'teachers.id', '=', 'students.teacher_id')
->where('teachers.id', $id)
->select('teachers.name AS teacher_name', 'students.name AS student_name', [ rest of columns])
->get();
However, you might want to look into Eloquent relationships, which will allow you to iterate through a teacher then all of that teacher's students, or vice versa.
You need to add before ->get()
->select('Teachers.name as teacherName', 'Students.name as studentName')
and than you can use
{{$vu_data[0]->teacherName}}
and
{{$vu_data[0]->studentName}}
As per your table structure one teacher has many students. Hence instead of using join you can use laravel relationships with hasMany :
Teacher has many students - Teacher Model :
public function students(){
return $this->hasMany(Students::class);
}
A student belongs to a teacher - Student Model :
public function teacher(){
return $this->belongsTo(Teacher::class);
}
Now you can get relationships like below :
Get all teachers with their students :
$teachers = Teacher::with('students')->get();
Get all students of a particular techer :
$teacher = Teacher::find($teacherId);
$students = $teacher->students;
Finally using this, you can convert this :
$vu_data = Teacher::join('Students', 'teachers.id', '=', 'students.teacher_id')
->where('teachers.id', $id)
->get();
return view('view_full')->with('vu_data',$vu_data);
To this :
$teacher = Teacher::find($id);
return view('view_full', compact('teacher'));
Then inside blade :
You can get teacher details : {{ $teacher->name }}
and students :
#if($teacher->students->count() > 0)
#foreach($teacher->students as $student)
{{ $student->name }}
#endforech
#endif
I've got a situation where I've got Posts, Users and Comments.
Each comment stores a post_id and a user_id. What I want to do is get all of a user's comments on a particular post, so that I can do a call like this:
$comments = Auth::User()->comments(post_id=x)->text
(where I know what x is)
I have:
User->HasMany(comments)
Comments->HasOne(User)
Comments->HasOne(Project)
Project->HasMany(comments)
I feel like there needs to be a where or a has or a wherehas or something thrown in.. the best I can manage is that I pull Auth::User()->comments into an array and then search through the array until I find the matching post ID.. that seems wasteful.
with doesn't apply any join, so you can't reference other table.
You can use this:
// User model
public function comments()
{
return $this->hasMany('Comment');
}
// Comment model
public function scopeForPost($query, $postId)
{
$query->where('post_id', $postId);
}
// then you can do this:
Auth::user()->comments()->forPost($postId)->get();
Alternatively you can eager load comments with constraint:
User::with(['comments' => function ($q) use ($postId) {
$q->where('post_id', $postId);
}])->find($someUserId);
// or exactly the same as above, but for already fetched user:
// $user .. or
Auth::user()->load(['comments' => function ($q) use ($postId) {
$q->where('post_id', $postId);
}]);
// then you can access comments for $postId just like this:
Auth::user()->comments; // collection
When you need to filter your relations, you just have to do it in your Eloquent query:
$data = User::with('posts', 'comments')
->where('users.id', Auth::User()->id)
->where('posts.id', $postID)
->get();
Then you can
foreach($data->comments as $comment)
{
echo $comment->text;
}
Your Comments table would have foreign keys Post_Id and User_ID
To Access all the comments of a particular post from a particular user , can you try this way?
Comment::select('comments.*')
->where('comments.user_id', Auth::user()->id)
->leftJoin('posts','posts.id','=','comments.post_id')
->leftJoin('users','users.id','=','comments.user_id')
->get();
Am sure there is better way to achieve it, but this should give you desired results.
Note use aliases if you have conflicting column names
Let me know if this worked.