how do i convert SQL query to laravel Eloquent? - sql

Question

What i want to do is convert this query , i want to use pagination but when i use query like this pagination not working
DB::select('SELECT *, ( ( weight * 400 ) + Making_charge) AS Sum FROM products WHERE '.$cat.' ='. $id.' ORDER BY sum ASC');
when i try to use pagination i get this error
Call to a member function links() on array (View:
i tried type casting but that did not work either
can anyone provide me valid reason or solution without disliking it
thank you

Answer 1

The reason why you are getting Call to a member function links() on array is because the QueryBuilder returns an array. Not a collection as Eloquent.
I changed your SQL query to use double quotes in order to use string interpolation, and the work sum to product_sum, since sum is a reserved word by mysql.
"SELECT *, (( weight * 400 ) + making_charge) as product_sum FROM products WHERE {$cat} = {$id} ORDER BY product_sum ASC";
Your query, using eloquent, will look as somethin like this:
Product::query()
->where($cat, $id)
->select(['*', DB::raw('(weight * 400 + making_charge) as product_sum')])
->orderBy('product_sum')
->get();
This query returns a collection. You can also paginate using laravel pagination:
$items_per_page = 10;
Product::query()
->where($cat, $id)
->select(['*', DB::raw('(weight * 400 + making_charge) as product_sum')])
->orderBy('product_sum') // The default direction is ASC
->paginate($items_per_page);