Laravel Eloquent：如何按产品类别和/或产品品牌过滤产品评论？

Question

I will describe this situation with more details:

I have a list of products where every product belongs to a certain category and to a certain brand. Some of the products can get reviewed by users.

On /reviews/ page in my Laravel application, I have a list of reviews and select boxes for category and brand along with search button of course.

If user doesn't choose category or brand, all reviews get displayed, paginated, and that's good.

The problem arises when user chooses either category or brand or both and tries to get all the reviews filtered that way.

Reviews table fields: ID, user_id(foreign key users.ID), product_id(foreign key products.ID), text
Products table fields: ID, category_id(foreign key categories.ID), brand_id(foreign key brands.ID), name
Categories table fields: ID, name
Brands table fields: ID, name
Users table fields: ID, username

When I'm listing reviews, I'm simply using:

$reviews = Review::orderBy('id', 'DESC')->paginate(5);

If I would like to filter reviews by user_id, that would be easy as the reviews table contains user_id column, but, how to filter them by product category and/or product brand?

Here are Review, Product and Category models:

<?php namespace App;

use Illuminate\Database\Eloquent\Model;

class Review extends Model {
    protected $fillable = [];

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

    public function user() {
        return $this->belongsTo('App\User');
    }
}

<?php namespace App;

use Illuminate\Database\Eloquent\Model;

class Product extends Model {

    protected $fillable = [];

    public function user() {
        return $this->belongsTo('App\User');
    }

    public function reviews() {
        return $this->hasMany('App\Review');
    }

    public function category() {
        return $this->belongsTo('App\Category');
    }

}


<?php namespace App;

use Illuminate\Database\Eloquent\Model;

class Category extends Model {
    protected $fillable = [];

    public function products() {
        return $this->hasMany('App\Product');
    }
}

If I use joins, then $review->user->id, $review->user->username, $review->id are not correct, I'm getting reviews.product_id as $review->id, and products.user_id as $review->user->id in blade template.

I was trying this join variant:

$reviews_query = Review::orderBy('reviews.id', 'DESC')
            ->Join('products', 'reviews.product_id', '=', 'products.id')
            ->Join('categories', 'products.category_id', '=', 'categories.id')
            ->Join('brands', 'products.brand_id', '=', 'brands.id')
            ->Join('users', 'reviews.user_id', '=', 'users.id')
            ->where('reviews.active', '=', 1)
            ->GroupBy('reviews.id')->paginate(5);

And this for filtering by category_id:

if (Input::has('category_id')){
    $category_id = Input::get('category_id');
    $reviews_query->where('categories.id', $category_id);
}

I'm not sure how to correctly address ambiguous ids such us product_id, review_id, user_id in blade template ($review->id, $review->user->id, all are messed up mutually)

Answer 1

Add hasManyThrough relationship in your category model

public function reviews() {
    return $this->hasManyThrough('App\Review', 'App\Product');
}

now you can have all reviews by a category like this

$category->reviews();

you can add other query clauses to it like

$category->reviews()->orderBy('id', 'DESC')->paginate(5);

Answer 2

Try this,

$reviews = DB::table('review')
->join('product', 'product.id', '=', 'review.product_id')
->Join('category', 'product.category_id', '=', 'category.id')
->orderBy('id', 'DESC')->paginate(5);

for more you can visit- Laravel join with 3 Tables

This may work for you.....

Answer 3

filter all reviews by a specific CategoryID then simply use ->

$categoryID = 1;
Categories::with(['products' => function($product){
        $product->with('reviews');
    }])->where('id', '=', $categoryID)->get();

also filter all reviews by a specific BrandID then

$brandID = 1;
Brands::with(['products' => function($product){
        $product->with('reviews');
    }])->where('id', '=', $brandID)->get();