class_name

[justqyx]

because of some reason,I have to do like this:

class Fabric < ActiveRecord::Base
has_many :fabric_material_records
end

class FabricMaterialRecord::Base
belongs_to :fabric
belongs_to :material, :class_name => "Fabric"
end

however,as the result:

FabricMaterialRecord.material_number_like("PP");
will give on the console:(It's error)
FabricMaterialRecord Load (0.1ms) SELECT fabric_material_records.* FROM fabric_material_records INNER JOIN fabrics ON fabrics.id IS NULL WHERE (fabrics.number LIKE '%PP%')

FabricMaterialRecord.fabric_number_like("PP")
will give(It's correct!)
FabricMaterialRecord Load (0.1ms) SELECT fabric_material_records.* FROM fabric_material_records INNER JOIN fabrics ON fabrics.id = fabric_material_records.fabric_id WHERE (fabrics.number LIKE '%PP%')

I'll have see one issue at #8, but nobody has given the solution!
Please help me, thanks!