with recursive
s1 as (
  select '112-233-445 95' as snils from rdb$database union all
  select '165-300-180 28' from rdb$database union all
  select '999-999-999 95' from rdb$database
)
,s2 as (
  select s1.snils, replace(substring(s1.snils from 1 for 11),'-','') n, right(s1.snils,2) to_check
  from s1
)
,r as(
  select 1 i from rdb$database union all select r.i+1 from r where r.i<9
)
,c as (
    select
         s2.snils
        ,s2.n
        ,s2.to_check
        ,sum((10-r.i) * cast( substring(s2.n from r.i for 1) as smallint )) dsum
    from s2 cross join r
    group by s2.snils,s2.n,s2.to_check
)
,d as (
    select
     c.snils
    ,c.n
    ,c.to_check
    ,iif( c.dsum < 100, c.dsum, iif(c.dsum in(100,101), 0,  coalesce(nullif(mod(c.dsum, 101), 100),0)  ) ) checked
    from c
)
select d.snils, d.to_check, d.checked, iif(d.to_check = d.checked, 'ok', 'x') result
from d;