how to get N records from a model per parent ? In laravel eloquent

How can i get n records from a model per parent in laravel eloquent.

For example lets say i have products table and categories table. And i want a list of all the products who's name starting with A but not more then 10 products per category.

My table structure is something like this.

products table

---------------------------------
id  | title | slug | category_id
----------------------------------

Category table

--------------
id  | title |
--------------

I tried to follow this example which is exactly what i want https://softonsofa.com/tweaking-eloquent-relations-how-to-get-n-related-models-per-parent/

But when i tried to query just like the example in the link after adding the scope in my product model . It throwing and sql error saying.

SQLSTATE[HY000]: General error: 1267 Illegal mix of collations (utf8mb4_unicode_ci,IMPLICIT) and (utf8mb4_0900_ai_ci,IMPLICIT) for operation '=' (SQL: select count(*) as aggregate from...

Can anyone please tell how i can get n results per related model or how can i fix this error.

via Chebli Mohamed