Re: GROUP BY overlapping (tsrange) entries - Mailing list pgsql-sql

 

 

2016-01-30 0:25 GMT+01:00 Andreas Joseph Krogh <andreas@visena.com>:

På fredag 29. januar 2016 kl. 20:33:08, skrev Misa Simic <misa.simic@gmail.com>:

 

 

2016-01-29 2:11 GMT+01:00 Andreas Joseph Krogh <andreas@visena.com>:

På fredag 29. januar 2016 kl. 02:02:46, skrev Michael Moore <michaeljmoore@gmail.com>:

It is unclear to me how you got from your input data to your expected output. If you are "trying to count() overlapping entries" then it would seem to me that you would only have only one value for the count. Either a range overlaps or it does not.

 

Oh, sorry, the count was in wrong order.

 

Let me explain,

insert into event(name, start_time, end_time)    values('a', '2015-12-20', NULL)        , ('a', '2015-12-20', '2015-12-31')        , ('a', '2015-12-25', '2016-01-01')        , ('b', '2015-11-20', '2015-11-24')        , ('c', '2016-02-01', '2016-02-03')        , ('c', '2016-02-01', '2016-02-04')
        , ('c', '2016-02-01', NULL)
;

All 'a', 'b' and 'c' have points in common, with count a=3, b=1, c=3.

 

Thanks.

 

 

I think data are not correct...

 

Expected result is the same as count() group by name...

 

But I guess you have included name column just to different ranges for overlap...

 

Yes, as I worte in the followup:

"Note that the 'name'-column here is just to explain what I'm after and that I have no such column."

 

But actually there is just 2 ranges:name b is 1 range, name a & c are second range. all overlaps by first range '2015-12-20, null) - it contains all records named as C ranges

 

Yes, my bad. Pretend the first range for 'a' was '2015-12-20" - "2015-12-27".

 

 

In that case, the result you can get by:

 

SELECT COUNT(1) FROM (

SELECT (SELECT tsrange(min(start_time), max(COALESCE(end_time, 'infinity'))) FROM event e WHERE e.tsrange && main.tsrange) as full_range 

FROM event main

) t

GROUP BY full_range

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