How to retrieve empty json array by Eloquent?

Question

I have table item which has a JSON column sku_purchase_price. There are some rows like that:

I tried to retrieve those rows from DB by Eloquent:

$items = Item::where('sku_purchase_price', '[]')->get();

but it returns a collection with zero results.

So, how to retrieve those row from DB by Eloquent?

user_5935198 · Answer

$items = Item::whereJsonLength('sku_purchase_price', 0)->get();

This works only with MySQL 5.7, PostgreSQL, SQL Server 2016, and SQLite 3.9.0 (with the JSON1 extension).