At step 2, for Split policy, you selected Duplicate. When you split a building made of Brick
material (domain code: 2) during the edit session in ArcMap, you will have two buildings
made from bricks. For Merge policy, you selected Default Value. Let's suppose you already
established the Default Value option for the BM (Building material) field to 0. When
you merge two buildings made of Brick material (domain code: 2) during the edit session in
ArcMap, you will have two buildings made of Unknown material (domain code: 0). The range
and coded values can be validated in the ArcMap edit session using the Validate Features
option from Editor present in the Editor toolbar. The Validate Features option helps you to
find mistaken attribute values in the sense that it is not a valid value.