对于您不想使用逐行方法的表中的列，请尝试以下一种方法：

with cte(n) as (
    select 1
    union all
    select n + 1 from cte where n < 9
)
select
    t.s1, t.s2,
    sum(
      case
      when substring(t.s1, c.n, 1) <> substring(t.s2, c.n, 1) then 1
      else 0
      end
    ) as diff
from test as t
    cross join cte as c
group by t.s1, t.s2

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