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with t as (
select v.*
from (values (convert(date, '2014-08-24'), convert(date, '2014-12-19')),
('2014-08-31', '2014-09-02'),
('2014-09-02', '2014-09-18'),
('2014-09-18', '2014-11-03'),
('2014-11-18', '2014-12-09')
) v(start_dte, end_dte)
)
select min(start_dte) as start_dte, max(end_dte) as end_dte
from (select t.*,
sum(case when prev_end_dte = start_dte then 0 else 1 end) over (order by start_dte) as grp
from (select t.*,
lag(end_dte) over (order by start_dte) as prev_end_dte
from t
) t
) t
group by grp;
| start_dte | end_dte |
|---|---|
| 24/08/2014 00:00:00 | 19/12/2014 00:00:00 |
| 31/08/2014 00:00:00 | 03/11/2014 00:00:00 |
| 18/11/2014 00:00:00 | 09/12/2014 00:00:00 |