We are confronting some issues when we want to search and filter child products.
Child products are missing some fields like categories and manufacturers which makes it quite hard to search/filter them.
We want to assign these fields but then we have the drawback that they will be always displayed in the category pages.
A great feature would be to have a setting letting us to display or not child products in the category (or other) pages.
I suppose that it is quite simple to be implemented by just adding a small where clause to check if the product_parent_id > 0
The same counts for the filter query, just check for the parent product id. There are examples in our code for that.
The problem is not in the query is in the views/layouts.
Why not offering the user the flexibility to assign all these fields (categories, manufacturers, etc) to the child products and decide which type of products (parent/child ,or all) will be loaded in the category pages, without being forced to do compromises in his data structure?