Add custom field to product attributes add/edit form and save value to DB?

Question

I added a custom field to attribute add/edit form using these instructions: https://magento.stackexchange.com/a/238731 and Magento 2.2.6 : Add custom field in product attribute add form - Is not render the database value on edit

So I created an extension with that code and I do see the new field in the product attribute add/edit form, but the value doesn't get saved.

So the part that's missing is how to save the value to the DB. How can I accomplish that?

Thank you

Answer 1

Please confirm first with table "sample_attribute", attribute has created or not.

If not then kindly refer below link :

https://www.mageplaza.com/magento-2-module-development/magento-2-add-product-attribute-programmatically.html