php - Laravel Eloquent and Multiple Joins

Question

I understand how to use Eloquent for basic queries and relationships, but I start getting confused when selecting information based on relationships in multiple tables.

For example, i can get the data I need from the database using the the query builder as follows:

    $data['products'] = DB::table('product')
    ->select('product.id', 'product.ref_num', 'productdetails.name')
    ->join('productdetails', function($join)
    {
        $join->on('product.id', '=', 'productdetails.product_id')
             ->where('productdetails.website_id', '=', '7');
    })
    ->leftJoin('product_category', function($join) use($submenu_id){
        $join->on('product.id', '=', 'product_category.product_id')
            ->where('product_category.category_id', '=', $submenu_id);
    })
    ->leftJoin('product_type', function($join) use($type_id){
        $join->on('product.id', '=', 'product_type.product_id')
            ->where('product_type.type_id', '=', $type_id);
    })
    ->get();

Basically, i'm getting data from the product and productdetails tables based on which category the product is part of and what type of product it is; These are defined by inner joins to pivot tables product_type and product_category.

Now assuming i have the eloquent relationships set up correctly, how would i go about doing this in Eloquent?

Here are the relevant parts of the Eloquent Models

Product

class Product extends Eloquent{

public function productdetails()
{
    return $this->hasMany('Productdetail');

public function categories()
{
    return $this->belongsToMany('Category', 'product_category', 'product_id', 'category_id');
}

public function types()
{
    return $this->belongsToMany('Producttype', 'product_type', 'product_id', 'type_id');
}
}

Product Details

class Productdetail extends Eloquent
{


public function product()
{
    return $this->belongsTo('Product');
}
}

ProductType

class ProductTypes extends Eloquent{


function products()
{
    return $this->belongsToMany('products', 'product_id', 'type_id', 'product_id');
}

Category

class Category extends Eloquent{

public function products()
{
    return $this->belongsToMany('product', 'product_category', 'category_id', 'product_id');
}
}

Thanks in advance

Answer 1

Assuming your relations are correct and related table names are: categories and types, this will do the job:

Product::with('productdetails')
    ->whereHas('categories', function ($query) use ($submenu_id) {
          $query->where('categories.id', '=', $submenu_id);
    })
    ->whereHas('types', function ($query) use ($type_id) {
          $query->where('types.id', $type_id); // side note: operator '=' is default, so can be ommited
    })
    ->get();

It will run 2 queries ( first for getting appropriate products, second for product details related to them) and return Eloquent Collection