Integrating Products from external MSSQL DB

Hi folks,

I have a WP-site running with posts and static pages.
On our buisness-server, there’s a mssql db up and running. it contains around 3000 products in different categories. they are organized as the following example:

Main-category —> Sub-category —> Product.

I already wrote a Codeigniter-app to accomplish my goal BUT i want to integrate it in wordpress.
What i want to do:

1. The user opens a wordpress-site from the main menu (e.g. Products)
2. The Main-Categorys get loaded and displayed dynamically (by MSSQL<–>PHP script)
3. The user clicks on a Main-category and gets to the Sub-categories. (In Codeigniter, i would pass the Category nicely via URI. E.g. https://www.mysite.com/products/MAIN-CATEGORY-SLUG/)
4. and so on … ww.mysite.com/products/MAIN-CATEGORY-SLUG/SUB-CATEGORY-SLUG/

Membership, Cart and Product-Details

I need a concept how to realise this with wordpress … maybe on of this?

• integrating codeigniter into wordpress for that specific task. (site-template would be a CI-view, possible??? what about the URI?)
• Dynamically create the Products as custom posts with nested categories (maybe a cronjob creates the custom-posts once a day)
• native php with arguments in the uri? i want it seo friendly!!!
• a shop plugin that is flexible enough to get the data from mssql ?

i know my question is not very structured, but i hope someone understands what i mean.

thx for the answers!!!
Apo