ar_raneem wrote:
in my buillding, i've got a long wall what i want it to get different materials.
You don't specify if you want different materials horizontal or vertically.
Duanes advice above applies more to vertical divisions in a wall (although you could break a wall down into horizontal parts if you wanted, but there is a better & easier way to do that).
For different materials horizontally you should consider using a complex profile assigned to a wall. You can individually split the wall into any number of components, apply a different material to each, and extrude everything along the whole length.
See this tech tip for an example -
