January 2011
3 posts
3 tags
calculating median values via mysql
Here is a quick mysql sql snippet that I used to calculate median values grouped by year…
select a.year, avg(a.rownum), avg(a.value) from (
select if(@current_year=year, @rownum:=@rownum+1, @rownum:=1) as rownum,
@current_year:=year as year, amount as value from (your_data_or_select) as amounts, (select
@rownum:=0) as r, (select @current_year:=0) as y order by year, amount) as a,
(select...
