find_missing_numbers_ranges.sql

select "sequence".id + 1 as start, min(fr.id) - 1 as stop
from "sequence"
    left outer join sequence as r on "sequence".id = r.id - 1
    left outer join sequence as fr on "sequence".id < fr.id
where r.id is null and fr.id is not null
group by "sequence".id, r.id;

select "blocks".number + 1 as start, min(fr.number) - 1 as stop
from "blocks"
    left outer join blocks as r on "blocks".number = r.number - 1
    left outer join blocks as fr on "blocks".number < fr.number
where r.number is null and fr.number is not null
group by "blocks".number, r.number;