Re: question about a select - Mailing list pgsql-general

From Cindy
Subject Re: question about a select
Date
Msg-id 9118.1065735764@stephanus.tlg.uci.edu
Whole thread Raw
In response to Re: question about a select  (Stephan Szabo <sszabo@megazone.bigpanda.com>)
Responses Re: question about a select  (Stephan Szabo <sszabo@megazone.bigpanda.com>)
List pgsql-general
Thanks for the speedy response!

Stephan Szabo writes:
 >On Thu, 9 Oct 2003, Cindy wrote:
 >
 >
 >> Text=# select distinct on (y_level) y_level, byteloc from
 >> citations_by_level where aid=543 and wid=1 order by byteloc;
 >> ERROR:  SELECT DISTINCT ON expressions must match initial ORDER BY
 >> expressions
 >
 >Maybe something like:
 >
 >select y_level from (select distinct on (y_level) y_level,
 >byteloc from citations_by_level where aid=543 and wid=1) tab order by
 >byteloc;

Hm...this seems to pick out the y_level with the largest byteloc
associated with it...I need the y_level with the smallest byteloc and
then sorted by that...lemme play this, but any other suggestions also
welcomed...

(EG, I got:
Text=# select y_level, byteloc from (select distinct on (y_level)
y_level, byteloc from citations_by_level where aid=543::smallint and
wid=1::smallint) tab order by byteloc;


 y_level | byteloc
---------+---------
 13      |   24017
 11      |   36231
 8       |   47240
 10      |   96777
 2       |  285678
 5       |  400212
 7,8     |  420879
...

but if you look at the raw data (or some of it):
---------+---------
 1       |      29
 1       |      84
 2       |     423
 3       |     827
 4       |    1005
 5       |    1169
 6       |    1530
 1       |    1698
 2       |    1988
 3       |    2284
 4       |    2460
 5       |    2638
 6       |    2924
 7       |    3155
 8       |    3396
 1       |    3673
 2       |    4095
 3       |    4387
 4       |    4699
 5       |    4944
 6       |    5055
 7       |    5406
 8       |    5704
 9       |    5996
 10      |    6349
 1       |    6578
 2       |    7110

I want

 1       |      29
 2       |     423
 3       |     827
 4       |    1005
 5       |    1169
 6       |    1530
 7       |    3155
 8       |    3396
 9       |    5996
 10      |    6349

etc...


--
Cindy
ctmoore@uci.edu

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