How to append many objects without appending materials [duplicate]

Question

Is there any option, to append many objects without appending their materials?

Example: I have scene1.blend with cube object and wood material. I append cube with wood to scene2.blend, where there also is cube and wood material.

Blender logically creates cube.001 and wood.001, but I don't want wood.001, I need Blender to use the existing wood material instead of creating a new copy.

I'm talking about thousands of objects and hundreds materials. For example now I have natural wood.## ... natural wood.017 and all are exactly the same, and I have few dozens of materials like this multiplied by 17 object copies.

My English is not very good and this is problem little bit hard to explain, so I hope you understand what I mean.

Answer 1

After importing the objects you can use a python script to remove the use of duplicate materials. As each duplicate gets a numeric extension we can test whether the material without the extension exists and use it if it does exist.

import bpy

mat_list = bpy.data.materials

for o in bpy.data.objects:
    for s in o.material_slots:
        if s.material.name[-3:].isnumeric():
            # the last 3 characters are numbers
            if s.material.name[:-4] in mat_list:
                # there is a material without the numeric extension so use it
                s.material = mat_list[s.material.name[:-4]]

Answer 2

Not really a solution to the append problem directly, more of a cleanup technique, but if you only have one material per object you can easily select all objects with the same base material name (say wood.001 wood.002 wood.003) by searching for wood in the outliner.

Just go to the Outliner and search for your material name, after searching press A over the list of search results to pre-select all displayed objects in that list, then Righ-Click over them and choose Select.

That should take care of selecting all of them in the 3D view. Now in the 3D view and without deselecting the previously selected objects Shift-Select the object with the original wood you want to use to make it the Active Object.

Alternatively you may instead change the material manually to the desired original wood on any of the search results by making it the Active Object first. (Just Shift-Select one of the already selected to make it active)

Afterwards you can press Ctrl + L Link > Materials to make them all use the same wood material instead.

(Bottom line here is Link > Materials works from the active object to the selection)