PS 1.7: Save AJAX Data from module on product page to DB

[Blackneron]

Hi,

I am building a PrestaShop module and can not save the product data to the DB (AJAX).

Characteristics of the module:

- PrestaShop version: >= 1.7.4.x
- Data is added to each of the products.
- Data input form is on the product page in the tab "Module".
- Form data should be saved to the database via AJAX call.

Actual state of the module:

- The module can be installed, has a configuration page and a form on the product page (of each product).

Unsolved problem:

- How to save the data from the product page to the database?
- Which workflow is necessary to get the data from the form into the DB?
- Which hooks/classes/methods have to be implemented for that?
- Is there a repository of an example module (Github, Bitbucket...) where I can see this?
- Example which only saves the data of 1 text field into the DB (via AJAX)?
- General guideline example like: Form data => Press Button => hookUpdateData => ajaxController...

Does anyone could help me with this?

Thanks a lot and have a nice day!