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
<alonup8tb@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.
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
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