Call to a member function where() on null error in laravel

@tykus the error occurs in this line

$fuel_ids = $inventory_data->where('ptype', 'oilgas','hydrogen')->pluck('id')->toArray();

@stephen waweru where is that line?

@tykus its in this showDocumentSupplierView($company_id) function but i didnt include it in the code coz my code was working when using ->get() because it showed all the data from the table but when i used ->find($company_id) to get data from this specific company id that's when i got this error

@stephen waweru don't you think it would be useful to share the relevant code?

Anyway, $inventory_data obviously is null

Question is... why do you use a Collection method (where) when the result of find is either null or a Model instance???

@stephen waweru Show the exact lines that are causing the error. And add ``` on the line before and after to format it properly

@tykus let me edit the question again..

@stephen waweru that'd be good

@tykus how can i fix it to get the products for each company instead of getting data for all the companies

@stephen waweru

but when i used ->find($company_id) to get data from this specific company id that's when i got this error

Where is ->find($company_id) in the code above????

@tykus my bad,,have a look i have edited it again

@stephen waweru this query seems wrong; you are trying to find one product instance using a Company id????

$inventory_data = product::whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen'])
    ->whereNotNull('name')
    ->whereIn('id', $ids)
    ->find($company_id);

As I mentioned before $inventory_data is null - probably because the $company_id is incorrectly being used to find one product instance!!! If you dd($inventory_data) immediately after that query; you will very likely see that the result is null.

@tykus yes i found out as null..i want to get data for that company,,how can i modify the code

@stephen waweru what is the relationship between product and company?

@tykus i have a included a pivot table that links the 2...here is the relationship in the company(merchant) model

class Merchant extends Model

{ protected $table = 'merchant'; protected $guarded = []; use SoftDeletes;

public function franchises(){
    return $this->belongsToMany(Franchise::class, 'franchisemerchant', 'franchisee_merchant_id', 'franchisee_merchant_id');
}

public function franchisemerchant(){
    return $this->hasMany(FranchiseMerchant::class, 'franchisee_merchant_id');
}

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

}

@stephen waweru a many-to-many relation... and you thought find was appropriate???? You need to learn some of the basics of using the framework...

@tykus i have changed the query to this in the function but still i get all the data from the table.the merchant products is a function i added in the products table which gets data from the merchadiseproducts table..is there any other way i can get data for a single merchant only instead of all the others.

public function merchantproducts(){ return $this->hasMany(merchantproduct::class, 'product_id', 'id'); }

''$inventory_data = product:: whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen'])-> whereNotNull('name')->whereIn('id', $ids)->with('merchantproducts')->get();''

@stephen waweru

1. what is the name of the belongs to many relationship on the product class to associate the product with the Company?
2. What variable/value do you have to identify the company in the method above?

@tykus this is the function that links the relationship in the merchant model

    function products(){
    return $this->belongsToMany('App\Models\product'); 
}

the function doesn't have a code to identify the company..but i have made a variable to get the data from the pivot table for each company

      $getdatafromproduct = DB::table('merchantproduct')->where('merchant_id',$company_id)->get();

..how can i get data using the function above for each company

@stephen waweru 🤷‍♂️ I asked you for the other side of that relationship.

How can you possibly identify the merchant whose products you need?

@tykus i am using this relationship in the product model

   public function merchantproducts(){
    return $this->hasMany(merchantproduct::class, 'product_id');
}

the merchantproduct here is the link table

@stephen waweru why do you have a model for the pivot table?

@stephen waweru suppose you have a conventional merchants relationship defined on the product Model, and products relation on the merchant Model:

// Product
public function merchants()
{
    return $this->belongsToMany(merchant::class, 'merchantproduct');
}

// Merchant
public function products()
{
    return $this->belongsToMany(product::class, 'merchantproduct');
}

Now there are two ways you could get the products:

$inventory_data = product::whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen'])
    ->whereNotNull('name')
    ->whereIn('id', $ids)
    ->whereHas('merchants', fn ($builder) => $builder->where('id', $company_id))
    ->get();

Or, if you have a merchant instance:

$merchant = merchant::find($company_id);
$inventory_data = $merchant->products()
    ->whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen'])
    ->whereNotNull('name')
    ->whereIn('id', $ids)
    ->get();

Choose one or the other.

@tykus i have used this one

   $merchant = merchant::find($company_id);

$inventory_data = $merchant->products() ->whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen']) ->whereNotNull('name') ->whereIn('id', $ids) ->get();

but am getting an error SQLSTATE[23000]: Integrity constraint violation: 1052 Column 'id' in where clause is ambiguous..what i have understood the 'id' here, ->whereIn('id', $ids), is the cause of the error..i have specified the table as ->whereIn('products.id', $ids) nd it throws an error unknown column

@stephen waweru format your code!

@stephen waweru do you have a global scope on the product model?

@tykus i dont have it..

@stephen waweru does your products table have an id column?

@tykus yes it has

  @tykus yes it has 

 public function up()
{
    Schema::create('product', function (Blueprint $table) {
        $table->bigIncrements('id');
        $table->string('systemid');
		$table->string('name')->nullable();
		$table->text('description')->nullable();
		// public/images/product/{product_id}/{photo_1}
		$table->string('photo_1')->nullable();
		// public/images/product/{product_id}/thumb/{thumbnail_1}
		$table->string('thumbnail_1')->nullable();
		$table->string('sku')->nullable();
        $table->enum('ptype',[
			'inventory','services','rawmaterial',
			'voucher','warranty','membership','drum','hydrogen',
			'customization','ecommerce','oilgas'
		])->default('inventory');
		// FK to prd_category.id
		$table->integer('prdcategory_id')->unsigned();
		// FK to prd_subcategory.id
		$table->integer('prdsubcategory_id')->unsigned();
		// FK to prdcategory.id
		$table->integer('prdprdcategory_id')->unsigned();$table->integer('brand_id')->unsigned();
        $table->softDeletes();
        $table->timestamps();
        $table->engine = "ARIA";
    });
}

@stephen waweru the table is called product - do you follow any conventions????

This should solve the ambiguity problem, but it doesn't explain why?

$inventory_data = $merchant->products()
    ->whereIn('ptype', ['inventory', 'rawmaterial', 'warranty', 'oilgas','hydrogen'])
    ->whereNotNull('name')
    ->whereIn('product.id', $ids)
    ->get();

@tykus thanks alot i have really learnt a lot