In response to A. Kretschmer :
> > please, suggest an idea how to implement this in SQL without writing a
> > procedure.
>
> There are a really nice additional contrib module from Jeff Davis,
> described here:
>
> http://thoughts.j-davis.com/2010/03/09/temporal-postgresql-roadmap/
>
short example, with your data:
test=# select * from rel_a;id | start_date | end_date | p
----+------------+------------+---------------------------------------------------- 1 | 01.01.2010 | 01.02.2010 |
[01.01.201000:00:00 CET, 01.02.2010 00:00:00 CET) 2 | 03.02.2010 | 04.03.2010 | [03.02.2010 00:00:00 CET, 04.03.2010
00:00:00CET)
(2 rows)
test=# select * from rel_a where contains(p, period('15.01.2010'::date, '15.02.2010'::date));id | start_date | end_date
|p
----+------------+----------+---
(0 rows)
test=# select * from rel_a where contains(p, period('15.01.2010'::date, '25.01.2010'::date));id | start_date |
end_date | p
----+------------+------------+---------------------------------------------------- 1 | 01.01.2010 | 01.02.2010 |
[01.01.201000:00:00 CET, 01.02.2010 00:00:00 CET)
(1 row)
The column p is created with:
test=# alter table rel_a add column p period;
and
test=# update rel_a set p = period(start_date, end_date);
Andreas
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Andreas Kretschmer
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