CH column metadata: esios.up_uof_crosswalk.up_code

# `esios.up_uof_crosswalk.up_code` REE programming unit (UP). - **category**: dimension - **common_pitfalls**: - Join on the code AND `day BETWEEN start_date AND end_date`: a UP can have several segments with different UOFs - No segment for a day means no evidence, not 'no UOF'. Coverage starts 2018 and ends at the last recomputation