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Finding missing values in sequence column
3+ messages / 3 participants
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* Finding missing values in sequence column
@ 2010-12-30 11:19 Lukasz Brodziak <lukasz.brodziak@gmail.com>
  2010-12-30 11:48 ` Re: Finding missing values in sequence column Szymon Guz <mabewlun@gmail.com>
  2010-12-30 18:49 ` Re: Finding missing values in sequence column Jasen Betts <jasen@xnet.co.nz>
  0 siblings, 2 replies; 3+ messages in thread

From: Lukasz Brodziak @ 2010-12-30 11:19 UTC (permalink / raw)
  To: pgsql-admin

Hello,

I have a problem with writing a select statement that would return
records for which difference in values of this and following ID is
bigger than 1. Example table
ID      Data
1       Text
2       Text2
5       Text5
23     Text23
24     TXT
25     RRRR

So I need to return rows with IDs 2,5,23.
-- 
Łukasz Brodziak
"What if everyting around You isn't quite as it seems,
What if all the world You think You know is an inelaborate dream
When You look at Your reflection is that all you want it to be
What if You could look right through the cracks
Would You find Yourself...... Find Yourself afraid to see"



^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Finding missing values in sequence column
  2010-12-30 11:19 Finding missing values in sequence column Lukasz Brodziak <lukasz.brodziak@gmail.com>
@ 2010-12-30 11:48 ` Szymon Guz <mabewlun@gmail.com>
  1 sibling, 0 replies; 3+ messages in thread

From: Szymon Guz @ 2010-12-30 11:48 UTC (permalink / raw)
  To: Lukasz Brodziak <lukasz.brodziak@gmail.com>; +Cc: pgsql-admin

On 30 December 2010 12:19, Lukasz Brodziak <lukasz.brodziak@gmail.com>wrote:

> Hello,
>
> I have a problem with writing a select statement that would return
> records for which difference in values of this and following ID is
> bigger than 1. Example table
> ID      Data
> 1       Text
> 2       Text2
> 5       Text5
> 23     Text23
> 24     TXT
> 25     RRRR
>
> So I need to return rows with IDs 2,5,23.
>

Hi,
sorry, I don't get it. If difference between current and following id should
be bigger than 1, then returned rows should be only 2 and 5. Not 23.

You can do it this way:

select lag
from
  (select
     id,
     lag(id) over (order by id)
   from x
   order by id) a
where
  id-lag > 1;

regards
Szymon

^ permalink  raw  reply  [nested|flat] 3+ messages in thread

* Re: Finding missing values in sequence column
  2010-12-30 11:19 Finding missing values in sequence column Lukasz Brodziak <lukasz.brodziak@gmail.com>
@ 2010-12-30 18:49 ` Jasen Betts <jasen@xnet.co.nz>
  1 sibling, 0 replies; 3+ messages in thread

From: Jasen Betts @ 2010-12-30 18:49 UTC (permalink / raw)
  To: pgsql-admin

On 2010-12-30, Lukasz Brodziak <lukasz.brodziak@gmail.com> wrote:
> Hello,
>
> I have a problem with writing a select statement that would return
> records for which difference in values of this and following ID is
> bigger than 1. Example table
> ID      Data
> 1       Text
> 2       Text2
> 5       Text5
> 23     Text23
> 24     TXT
> 25     RRRR
>
> So I need to return rows with IDs 2,5,23.

SELECT id FROM Example EXCEPT SELECT id-1 FROM Example;

select * FROM Example WHERE id+1 NOT IN ( SELECT id FROM Example );





> -- 
> Łukasz Brodziak
> "What if everyting around You isn't quite as it seems,
> What if all the world You think You know is an inelaborate dream
> When You look at Your reflection is that all you want it to be
> What if You could look right through the cracks
> Would You find Yourself...... Find Yourself afraid to see"
>


-- 
⚂⚃ 100% natural



^ permalink  raw  reply  [nested|flat] 3+ messages in thread


end of thread, other threads:[~2010-12-30 18:49 UTC | newest]

Thread overview: 3+ messages (download: mbox mbox.gz follow: Atom feed)
-- links below jump to the message on this page --
2010-12-30 11:19 Finding missing values in sequence column Lukasz Brodziak <lukasz.brodziak@gmail.com>
2010-12-30 11:48 ` Szymon Guz <mabewlun@gmail.com>
2010-12-30 18:49 ` Jasen Betts <jasen@xnet.co.nz>

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