for instance CalifCrk | CalCrk | 1996-10-18 | 188 CalifCrk | CalCrk | 1996-08-23 | 183 CalifCrk | CalCrk | 1996-07-29 | 201 CalifCrk | CalCrk | 1996-09-27 | 185
188 is the biggest number for 1996-10-18 calcrk califcrk, and so on down the line. You need to eliminate the date column in the query, or whatever fits your requirements. On Mon, Oct 10, 2011 at 6:24 PM, Henry Drexler <alonup...@gmail.com> wrote: > you are also grouping by sample date, those are the largest values for the > criteria you have set out in the group by. > > > > On Mon, Oct 10, 2011 at 6:17 PM, Rich Shepard <rshep...@appl-ecosys.com>wrote: > >> I'm trying to query the table to extract the single highest value of a >> chemical by location and date. This statement gives me all the values per >> stream, site, and date: >> >> SELECT str_name, site_id, sample_date, max(quant) FROM chemistry WHERE >> hydro >> = 'Humboldt' group by str_name, sample_date, site_id order by str_name, >> site_id; >> >> I'm not seeing why this doesn't work; the top few lines of output are: >> >> CalifCrk | CalCrk | 1996-10-18 | 188 >> CalifCrk | CalCrk | 1996-08-23 | 183 >> CalifCrk | CalCrk | 1996-07-29 | 201 >> CalifCrk | CalCrk | 1996-09-27 | 185 >> >> when what I want is only the third line. >> >> A clue to the correct syntax is solicited. I'm sure it's something simple >> that I'm just not seeing. >> >> Rich >> >> -- >> Sent via pgsql-general mailing list (pgsql-general@postgresql.org) >> To make changes to your subscription: >> http://www.postgresql.org/**mailpref/pgsql-general<http://www.postgresql.org/mailpref/pgsql-general> >> > >
