PyQt, Open a Table when a row is selected populating it with the row values

[rarevesselt]

Ok, it creates a database with no entries.

If there are entries then you want to fill the ComboBoxes? Or the table?

I have a DB Viewer on github that shows how to load a database into QTableWidget

After the the comboBoxes are filled correctly it will saved in QtableWidget in the database.
There are entries in the database in QtableWidget.
The columns are product_id,product_name,inventory_received,starting_inventory,product_price and values for each rows.The content of my database user.db is shown in the file but I intended to add price.

I have three comboboxes
first comboBox is product id
second comboboxes is product_name
third comboBoxes is price.

I want the second Combobox to list all the product.That is working perfectly.
I want the first comboBox to reflect the product_id of the selected product_name.
I want the third comboBox to reflect the price of the selected product_name.
How can I achieve this behavior?I have checked out your work on GitHub.But, I am not getting the database to work on my side even when add a database on my system into the path.