sql - Min function in postgresql -


i trying find division lowest population density did following:

select p.edname, min((p.total_area*1000)/p.total2011) "lowest population density" eds_census2011 p group p.edname having count (*)> 1

total_area multiplied 1000 (so in square metres) , divide total population. want 1 record displaying division (edname) , population density wich calculated (min((p.total_area*1000)/p.total2011)), instead records - not sorted...

the problem have group edname, if leave out group by , having lines error. appriciated!

try

select edname, (total_area*1000/total2011) density   eds_census2011  (total_area*1000/total2011) = (select min(total_area*1000/total2011) eds_census2011)

sqlfiddle

a 'return 1 row' rule enforced using limit 1 if it's necessary


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