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select region, count(*),
round(count(*) * 1.0 / sum(count(*)) over (), 2) as rr,
round(ratio_to_report(count(*)) over(),2) as rr
from (select 'a' as region from dual union all
select 'a' as region from dual union all
select 'a' as region from dual union all
select 'b' as region from dual
) x
group by rollup(region)
| REGION | COUNT(*) | RR | RR |
|---|---|---|---|
| a | 3 | .38 | .38 |
| b | 1 | .13 | .13 |
| null | 4 | .5 | .5 |
select region, count(*),
round(count(*) * 1.0 / sum(case when grouping_id(region) = 0 then count(*) end) over (), 2) as rr,
coalesce(round(ratio_to_report(case when grouping_id(region) = 0 then count(*) end) over(), 2), 1) as rr
from (select 'a' as region from dual union all
select 'a' as region from dual union all
select 'a' as region from dual union all
select 'b' as region from dual
) x
group by rollup(region)
| REGION | COUNT(*) | RR | RR |
|---|---|---|---|
| a | 3 | .75 | .75 |
| b | 1 | .25 | .25 |
| null | 4 | 1 | 1 |