I've 3 tables:
Courses (have category_id)
Authors
Categories (of courses)
In my Authors model I've added:
public function courses () {
return $this->belongsToMany('App\Course', 'courses2authors')->where('status','=', 1);
}
"courses2authors" is the pivot table.
Then in my controller I retrieve courses info with:
$authors = Author::where('status', '=', 1)->orderBy('pos')->with('courses')->get();
It's ok but I've only the category_id in ->courses, how to add category name in the model relationship.
I try something like:
return $this->belongsToMany('App\Course', 'courses2authors')
->where('status','=', 1)->join('categories', 'categories.id', '=',
'courses.category_id')->select('categories.name as categoria');
But in this way in take only the category name and not the course data.
You can define belongsTo relationship in Course Model with Categories.
Course Model
public function categories () {
return $this->belongsTo('App\Categories', 'category_id');
}
While retrieving Author with Courses then you can use like this. (Controller code)
$authors = Author::where('status', '=', 1)->orderBy('pos')
->with('courses',function($query){
$query->with('categories);
})->get();
if you don't want to use like this then you can set $with attribute in Courses Model.
protected $with = ['categories']; // default with define here.
Use in controller :-
$authors = Author::where('status', '=', 1)->orderBy('pos')
->with('courses')->get();
Related
How to write this code in eloquent method ?
$product = DB::table('products')
->join('purchase', 'products.id', '=', 'purchase.id')
->join('sales', 'purchase.id', '=', 'sales.id')
->select('sales.*', 'purchase.*','products.*')
->get();
Create model Product and add one to many relationship with Purchase in Product model.
public function purchases()
{
return $this->hasMany('App\Models\Purchase');
}
Create model Purchase and add one to many relationship with Sale in Purchase model.
public function sales()
{
return $this->hasMany('App\Models\Sale');
}
Create model Sale.
You can retrieve data using following statement.
$products = Product::with('purchases.sales')->get();
Note: I am assuming the relationship as one to many you can also declare as per your data, also you can define one to many inverse relationship, please refer to laravel docs https://laravel.com/docs/8.x/eloquent-relationships#one-to-many.
You will get purchases and sales data in different key so you can use below syntax to loop over it.
foreach ($products as $product) {
foreach ($product->purchases as $purchase) {
//Purchase data for current product
foreach($purchase->sales as $sale){
//Sale data for current purchase
}
}
}
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 have a Student in the users table, Parent is in the same table, and that Parent is the parent of that Student.
The Student has a Schedule in the schedules table.
How I can write hasMany and belongsTo to get the proper relation like in following custom query which works fine:
$schedules = DB::table('users')
->join('schedules', 'users.id', '=', 'schedules.studentID')
->select('users.*', 'schedules.*', 'users.fname as fname', 'users.lname as lname')
->where('users.parent_id',$request->id)
->where('schedules.status','1')
->where('schedules.status_dead','0')
->whereIn('schedules.std_status',[1, 2])
->get();
As shown in the image below:
Before the relationship lets create parent scope and find student more elegant way
User Model
public function scopeByParent($query,$parentId){
return $query->where("parent_id",$parentId);
}
Above scope provide us to get user or users by parent id.
Then create relationships.
User Model
public function schedules(){
return $this->hasMany("App\Schedule","studentID","id");
}
Schedule Model
public function users(){
return $this->belongsTo("App\User","id","studentID");
}
Then lets create our query using above scope and relation.
User::with(["schedules" => function ($query) {
$query->whereStatusAndStatusDead(1, 0)
->whereIn('std_status', [1, 2]);
}])
->byParent($request->id)
->get();
i have three table one is category table and another is product table and one more product_to_category table, and it has only product_id and category_id column.
Now i want to get top 10 categories with maximum number of product, with details of 10 products from each category.
What i wrote is
$result = ProductToCategory::groupBy('category_id')->with(['product',function($q){
$q->take(10);
}])->orderBy('category_id)->take(10);
But this is not working.How to write this query properly
Can anyone please help. ty
Model relations
For Product model
public function category(){
return $this->belongsTo(ProductToCategory::class);
}
For Category model
public function products()
{
return $this->hasMany(ProductToCategory::class);
}
For ProductToCategory model
public function product()
{
return $this->hasMany(Product::class);
}
public function category()
{
return $this->belongsTo(Category::class);
}
The most efficient way would be using a raw SQL query because you can't filter products by using eager loading constraint.
But if you want an Eloquent solution anyway, define the relationships:
In the Product model:
public function categories()
{
return $this->belongsToMany(Category::class, 'product_to_category');
}
And in the Category model:
public function products()
{
return $this->belongsToMany(Product::class, 'product_to_category');
}
Then you'll have two options, both have their pros and cons:
1. This code will execute just 2 queries but will use more memory. You could get top ten categories with their products:
$categories = Category::withCount('products')->latest('products_count')->take(10)->with('products')->get();
And then keep only first ten products:
$categories->transform(function($category) {
$topProducts = $category->products->take(10);
unset($category->products);
$category->products = $topProducts;
return $category;
});
2. This solution will create 12 queries but will save the memory:
$categories = Category::withCount('products')->latest('products_count')->take(10)->get();
$categories->transform(function($category) {
$category->products = Product::whereHas('categories', function($q) use($category) {
$q->where('id', $category->id);
})
->take(10)
->get();
return $category;
});
Here is the DB facade version:
$tenPopularTags = DB::table('product_to_category')
->join('category', 'product_to_category.category_id', '=', 'category.id')
->select(DB::raw('count(product_to_category.category_id) as repetition, question_tag.tag_id'))
->groupBy('product_to_category.category_id')
->orderBy('repetition', 'desc')->take(10)
->get();
However I like #Alexey Mezenin way of doing it. Because that is the cleaner way have customized it a bit:
$tenCategories = Category::withCount('products')->orderBy('questions_count', 'DESC')->take(10)->get();
Have used both in my project blog with post and categories relationship and it works!
I was working with Laravel and got stuck in a situation. I have following models:
Category
Product
CategoryProduct
CategoryProduct holds the information about which product belongs to which category (a product may belong to multiple categories).
Now, when I want to load all products belonging to a particular category, I need to run query on Product and CategoryProduct which is where I'm stuck.
I gave it the following try but was unsuccessful:
$products = Product::where('status', '=', 'active')
->where('category_id', '=', $category_id)
->take($count)
->skip($skip)
->get();
Obviously, it will say that category_id is not a column.
Here is my DB & Model structure:
categories table
id,
name,
etc.
products table
id,
name,
sku,
etc.
category_products table
id,
product_id, ( Foreign key to Product.id )
category_id, ( Foreign key to Category.id )
etc.
Product model
class Product extends Eloquent {
protected $table = 'products';
protected $hidden = array();
public static $rules = array('name' => 'required|min:3');
}
Category model
class Category extends Eloquent {
protected $table = 'categories';
public static $rules = array('name' => 'required|min:3');
}
CategoryProduct model
<?php
class CategoryProduct extends Eloquent {
protected $table = 'category_products';
public function product()
{
return $this->belongsTo('Product');
}
public function category()
{
return $this->belongsTo('Category');
}
}
Update
A new question on this
I'm trying to display products. If category is not passed (value is -1), then I will show all products, otherwise I will show products from the passed category.
Now, when I show all products, those products may already exist in a category. I want to display ticked checkbox for products that are already in a category. I'm doing something like this:
if($category_id==-1)
$products = Product::where('status', '=', 'active')->take($count)->skip($skip)->get();
else{
$products = Product::whereHas('categories', function($q) use ($category_id)
{
$q->where('category_id', $category_id);
})->where('status', 'active')
->take($count)
->skip($skip)
->get();
}
The table category_products have product_id, category_id as columns.
Now, the query:
$products = Product::where('status', '=', 'active')->take($count)->skip($skip)->get();
will pick products only from products table. If I check each product for its existence in category_products, then there will be too many database queries for large number of products.
Any idea, how to achieve this. I hope I was able to clear my situation. Thanks
The CategoryProduct model should not be necessary unless you have additional fields besides product_id and category_id which point to other relationships.
What is necessary are the methods for setting up the relationship on the Category and Product models.
In Category, add the relationship function...
public function products()
{
return $this->belongsToMany('Product', 'category_products');
}
In your Product model, do the same for categories.
public function categories()
{
return $this->belongsToMany('Category', 'category_products');
}
Then you can query for your active products that belong to that category using your relationship method and whereHas()
$products = Product::whereHas('categories', function($q) use ($category_id)
{
$q->where('id', $category_id);
})->where('status', 'active')
->take($count)
->skip($skip)
->get();
You don't need a model for a pivot table in Many-to-Many relationships. Look at this section of the Eloquent documentation for further explanation.
You still need to create a migration to set up the pivot table (or do it manually if you don't use migrations), but not a model. Instead, create a function for Category to designate the relationship:
public function products()
{
return $this->belongsToMany('App\Product', 'category_products');
// - You might need to adjust the namespace of App\Product
// - category_products refers to the pivot table name
}
Likewise, Product needs a similar public function.
Then you're able to do it the other way around, by finding the category and then listing all its related products:
$products = Category::find($category_id)
->products()
->where('status', 'active')
->take($count)
->skip($skip)
->get();
This question could also be relevant to yours.