您正在重复列别名。你打算这样吗?
select (case when (z.mso_group_id = '3' and z.model_id = '22887081') then coalesce(level_2_id,996) when (z.mso_group_id = '4' and z.model_id = '22911859') then coalesce(level_2_id,997) when (z.mso_group_id = '5' and z.model_id = '22915074') then coalesce(level_2_id,998) when (z.mso_group_id = '2' and z.model_id = '22908275') then coalesce(level_2_id,999) end) as level_2_idfrom database_name;



