Re: grouping subsets

Yes. This is somewhat more complicated because it has more constraints.
I've noticed that a given combination doesn't appear with holes on a certain
day.

For ex, on a daily basis, we have every three key combinations together.

We dont have things like
2010-7-01 1726 3212 1428
2010-7-01 1726 3212 1428
... 318 1846 1012
2010-7-01 1726 3212 1428

Can I assume that, for a certain day , the records for the same three
combination are all together? There is just one set per day for a given
combination?

Or is it possible to have the same combination on one day with several sets?

Best,
Oliveiros

----- Original Message -----
From: "Rainer Stengele" <rainer(dot)stengele(at)diplan(dot)de>
Newsgroups: gmane.comp.db.postgresql.sql
To: "Oliveiros d'Azevedo Cristina" <oliveiros(dot)cristina(at)marktest(dot)pt>
Cc: <>
Sent: Thursday, July 29, 2010 10:41 AM
Subject: Re: grouping subsets

> Howdy Cristina,
>
> unfortunately things are more complicated. I have inserted an excerpt of
> the real data here:
>
> ================================================================================
> TableID MasterID dtBegin dtEnd
> idR idL idB consumption
> 4057312 295530 2010-07-01 00:59:21.077 2010-07-01
> 01:32:59.670 1726 3212 1428 279
> 4061043 295574 2010-07-01 01:59:31.137 2010-07-01
> 02:32:09.373 1726 3212 1428 183
> 4083397 295838 2010-07-01 07:57:51.327 2010-07-01
> 08:28:28.117 318 1846 1012 30
> 4090858 295920 2010-07-01 09:52:33.777 2010-07-01
> 10:31:34.393 318 1846 1012 487
> 4094589 295961 2010-07-01 10:47:59.370 2010-07-01
> 11:32:20.903 318 1846 1012 472
> 4098330 296013 2010-07-01 11:58:53.890 2010-07-01
> 12:31:35.730 318 1846 1012 195
> 4102069 296058 2010-07-01 12:36:19.170 2010-07-01
> 13:32:13.950 318 1846 1012 338
> 4105809 296102 2010-07-01 13:58:53.170 2010-07-01
> 14:02:57.710 318 1846 1012 105
> 4109555 296150 2010-07-01 14:59:11.663 2010-07-01
> 15:32:33.810 318 1846 1012 187
> 4113305 296194 2010-07-01 15:59:01.797 2010-07-01
> 16:02:27.260 318 1846 1012 108
> 4117048 296238 2010-07-01 16:20:47.997 2010-07-01
> 17:32:49.367 318 1846 1012 179
> 4120791 296282 2010-07-01 17:58:27.657 2010-07-01
> 18:29:01.733 318 1846 1012 256
> 4128291 296370 2010-07-01 19:54:17.687 2010-07-01
> 20:32:53.850 318 1846 1012 239
> 4132044 296413 2010-07-01 20:31:37.653 2010-07-01
> 21:29:13.497 318 1846 1012 39
> 4135797 296458 2010-07-01 21:59:13.983 2010-07-01
> 22:32:46.503 318 1846 1012 157
> 4139572 296506 2010-07-01 22:58:49.530 2010-07-01
> 23:32:22.543 318 1846 1012 218
> 4142941 296554 2010-07-01 23:59:13.857 2010-07-02
> 00:32:30.390 318 1846 1012 248
> 4146289 296598 2010-07-02 00:58:55.763 2010-07-02
> 01:32:41.983 318 1846 1012 204
> 4149616 296642 2010-07-02 01:46:57.357 2010-07-02
> 02:32:56.983 318 1846 1012 42
> 4152952 296686 2010-07-02 02:55:19.653 2010-07-02
> 03:32:28.013 318 1846 1012 135
> 4156289 296730 2010-07-02 03:43:52.777 2010-07-02
> 04:32:55.250 318 1846 1012 743
> 4159624 296774 2010-07-02 04:43:15.310 2010-07-02
> 05:32:44.547 318 1846 1012 277
> 4162961 296817 2010-07-02 05:58:59.483 2010-07-02
> 06:32:37.340 318 1846 1012 121
> 4166303 296862 2010-07-02 06:58:50.733 2010-07-02
> 07:32:39.113 318 1846 1012 239
> 4172981 296950 2010-07-02 07:28:55.293 2010-07-02
> 09:33:01.200 318 1846 1012 512
> 4176322 296993 2010-07-02 09:59:04.607 2010-07-02
> 10:33:01.903 318 1846 1012 139
> 4179667 297038 2010-07-02 10:55:27.760 2010-07-02
> 11:32:56.560 318 1846 1012 722
> 4183012 297082 2010-07-02 11:59:33.650 2010-07-02
> 12:32:14.700 318 1846 1012 163
> 4186351 297126 2010-07-02 12:23:45.997 2010-07-02
> 13:32:59.500 318 1846 1012 284
> 4189689 297169 2010-07-02 13:44:21.253 2010-07-02
> 14:18:05.080 318 1846 1012 254
> 4196371 297258 2010-07-02 16:16:19.123 2010-07-02
> 16:32:53.437 1706 3541 1511 161
> 4199720 297301 2010-07-02 16:59:35.127 2010-07-02
> 17:32:57.950 1706 3541 1511 250
> 4203068 297346 2010-07-02 17:59:34.027 2010-07-02
> 18:32:54.337 1706 3541 1511 302
> 4206413 297389 2010-07-02 18:59:28.730 2010-07-02
> 19:32:37.950 1706 3541 1511 276
> 4209758 297434 2010-07-02 19:54:00.243 2010-07-02
> 20:32:57.433 1706 3541 1511 209
> 4213102 297473 2010-07-02 20:49:10.963 2010-07-02
> 21:30:44.540 1706 3541 1511 76
> 4216447 297511 2010-07-02 21:59:34.810 2010-07-02
> 22:33:00.603 1706 3541 1511 287
> 4219818 297569 2010-07-02 22:56:52.750 2010-07-02
> 23:59:31.607 1706 3541 1511 1877
> 4219819 297570 2010-07-02 23:59:21.577 2010-07-03
> 00:54:40.153 1706 3541 1511 1798
> 4219821 297572 2010-07-03 00:48:03.310 2010-07-03
> 01:59:37.920 1706 3541 1511 1125
> 4219823 297574 2010-07-03 01:51:01.057 2010-07-03
> 02:59:45.433 1706 3541 1511 1629
> 4219820 297571 2010-07-03 02:59:29.393 2010-07-03
> 03:59:54.920 1706 3541 1511 2462
> 4219822 297573 2010-07-03 03:59:18.663 2010-07-03
> 04:01:48.810 1706 3541 1511 70
> 4225738 297656 2010-07-03 06:13:34.980 2010-07-03
> 06:28:09.697 1726 3212 1428 46
> 4228694 297695 2010-07-03 06:59:15.560 2010-07-03
> 07:32:45.653 1726 3212 1428 251
> 4231649 297733 2010-07-03 07:59:11.937 2010-07-03
> 08:32:57.217 1726 3212 1428 284
> 4234604 297771 2010-07-03 08:57:00.357 2010-07-03
> 09:32:47.903 1726 3212 1428 227
> 4237559 297809 2010-07-03 09:59:19.813 2010-07-03
> 10:33:02.063 1726 3212 1428 285
> 4261156 298596 2010-07-04 22:59:09.863 2010-07-04
> 23:33:45.530 1726 3212 1428 1286
> 4264114 298646 2010-07-04 23:59:16.967 2010-07-05
> 00:33:08.107 1726 3212 1428 297
> 4267067 298690 2010-07-05 00:59:15.187 2010-07-05
> 01:32:48.300 1726 3212 1428 333
> 4270023 298734 2010-07-05 01:59:02.497 2010-07-05
> 02:32:48.780 1726 3212 1428 270
> 4272977 298778 2010-07-05 02:41:43.737 2010-07-05
> 03:32:56.043 1726 3212 1428 317
> 4275927 298822 2010-07-05 03:59:17.027 2010-07-05
> 04:33:14.947 1726 3212 1428 1623
> ================================================================================
>
> Description:
> 1. Column: some ID
> 2. Column: reference to another table
> 3. and 4. column: timestamp from/to of the item
> 5. Column: ID R
> 6. Column: ID L
> 7. Column: ID B
> 8. Column: Sum of components
>
> Requirement:
> Sum over all components (from column 8) for each combination of ID R, ID
> L, ID B, but (!)
> rows with same keys (R,L,B) should be summed up only until the keys
> change.
> Do not sum up the components for identical keys, if there are other keys
> between them.
>
> Example result:
>
> idR idL idB SUM
> 1726 3212 1428 462
> 318 1846 1012 ...
> 1706 3541 1511 ...
> 1726 3212 1428 ...
>
>
> Note that the first and last entry here has the same keys
>
> Maybe you find a similar monster SQL solving such a requirement.
> Thanks for considering!
>
> Rainer
>
>
>
> Am 27.07.2010 12:37, schrieb Oliveiros d'Azevedo Cristina:
>> Howdy, Rainer.
>>
>> It's been a while, so I don't know if you are still interested in this
>> problem or if you, in the meantime, found yourself a solution,
>> but I've tried this on a local copy of the example you provided and it
>> seems to work.
>>
>> The problem is that I suspect that if you have several thousands of
>> records on your table it will become slow...
>>
>> Best,
>> Oliveiros
>>
>> SELECT SUM(tudo.parcela),tudo.a
>> FROM
>> (
>> SELECT fo.parcela,fo.a,fo.b,fo.c,MIN(th.c) as d
>> FROM
>> (
>> SELECT se.a as parcela,se.b as a,se.c as b, MAX(pr.c) as c
>> FROM
>> yourTable se
>> LEFT JOIN
>> (
>> SELECT a.*
>> FROM yourTable a
>> JOIN yourTable b
>> ON (b.b <> a.b)
>> AND ((age(a.c,b.c) = '1 day'::interval)
>>
>> )
>> ) pr
>> ON pr.b = se.b
>> AND se.c >= pr.c
>> GROUP BY se.a,se.b,se.c
>> ) fo
>> LEFT JOIN
>> (
>> SELECT a.*
>> FROM yourTable a
>> JOIN yourTable b
>> ON (b.b <> a.b)
>> AND ((age(a.c,b.c) = '-1 day'::interval)
>> )
>> ) th
>> ON fo.a = th.b
>> AND fo.b <= th.c
>> GROUP BY fo.parcela,fo.a,fo.b,fo.c
>> ) tudo
>> GROUP BY tudo.a,tudo.c,tudo.d
>>
>>
>>
>>
>> To: <pgsql-sql(at)postgresql(dot)org>
>> Sent: Thursday, July 22, 2010 9:09 AM
>> Subject: [SQL] grouping subsets
>>
>>
>>> Hi,
>>>
>>> having a table similar to
>>>
>>> | 1 | B | [2010-07-15 Do] |
>>> | 1 | B | [2010-07-16 Fr] |
>>> |---+---+-----------------|
>>> | 2 | C | [2010-07-17 Sa] |
>>> | 2 | C | [2010-07-18 So] |
>>> |---+---+-----------------|
>>> | 1 | B | [2010-07-19 Mo] |
>>> | 1 | B | [2010-07-20 Di] |
>>> | 1 | B | [2010-07-21 Mi] |
>>> | 1 | B | [2010-07-22 Do] |
>>> |---+---+-----------------|
>>> | 3 | D | [2010-07-23 Fr] |
>>>
>>> a simple group by gives me:
>>>
>>> | 6 | B |
>>> | 4 | C |
>>> | 3 | D |
>>>
>>>
>>> What I want to get is the values grouped by "subset", where a subset is
>>> a set of rows with identical column until the colum changes.
>>> Is there a way to get
>>>
>>> | 2 | B |
>>> | 4 | C |
>>> | 4 | B |
>>> | 3 | D |
>>>
>>> by SQL only?
>>>
>>> - Rainer
>>>
>>>
>>>
>>>
>>>
>>> --
>>> Sent via pgsql-sql mailing list (pgsql-sql(at)postgresql(dot)org)
>>> To make changes to your subscription:
>>> http://www.postgresql.org/mailpref/pgsql-sql
>>
>>