Voici une démo SQLFiddle Tout d'abord, créez des tables temporaires pour simplifier les requêtes, bien que vous puissiez placer ces requêtes de création dans des requêtes finales et le faire sans tables temporaires :
create table t as select * from
(
select null s ,"start"-1 as e from data
union all
select "start" s,null e from data
union all
select "end"+1 s ,null e from data
union all
select null s ,"end" e from data
) d where exists (select "start"
from data where d.s between data."start" and data."end"
or d.e between data."start" and data."end"
);
--Operation 1 - Disjoined Result
create table t1 as select s,e,e-s+1 width from
(
select distinct s,(select min(e) from t where t.e>=t1.s) e from t t1
) t2 where t2.s is not null and t2.e is not null;
--Operation 2 - Reduced Result
create table t2 as
select s,e,e-s+1 width from
(
select s,(select min(d2.e) from t1 d2 where d2.s>=d.s and not exists
(select s from t1 where t1.s=d2.e+1) ) e
from
t1 d where not exists(select s from t1 where t1.e=d.s-1)
) t2;
--Temp table for Operation 3 - Gaps
create table t3 as
select null s, s-1 e from t2
union all
select e+1 s, null e from t2;
Voici maintenant les requêtes :
--Operation 1 - Disjoined Result
select * from t1 order by s;
--Operation 2 - Reduced Result
select * from t2 order by s;
--Operation 3 - Gaps
select s,e,e-s+1 width
from
(
select s,(select min(e) from t3 where t3.e>=d.s) e from t3 d
) t4 where s is not null and e is not null
order by s;
