您可以尝试：

• 取消透视数据并保持每列的顺序，即Column_A顺序为1，Column_B顺序为2，依此类推。
• 使用ROW_NUMBER()函数对列值不为空的非透视数据进行处理，以获得不包含空值的新顺序。
• 使用上一步中定义的行号对数据进行条件聚合透视以获得所需的输出。

with t as
(
  select id, Column_A as col, 1 as ord from table_name
  union all
  select id, Column_b, 2 from table_name
  union all
  select id, Column_c, 3 from table_name
  union all
  select id, Column_d, 4 from table_name
  union all
  select id, Column_e, 5 from table_name
  union all
  select id, Column_f, 6 from table_name
),
t2 as
(
  select *, 
    row_number() over (partition by id order by ord) rn
  from t where col is not null
)

select id,
       max(case when rn =1 then col end) Column_A,
       max(case when rn =2 then col end) Column_B,
       max(case when rn =3 then col end) Column_C,
       max(case when rn =4 then col end) Column_D,
       max(case when rn =5 then col end) Column_E,
       max(case when rn =6 then col end) Column_F
from t2 
group by id
order by id

请参见demo。