in reply to Re: array of arrays calculationsin thread array of arrays calculations
SELECT h.e_id, h.cus, h.gd1-ifnull(t.gd1,0) as dif1, h.gd2-ifnull(t.gd2,0) as dif2 FROM tabla1 h left join tabla2 t on h.e_id = t.e_id and h.cus = t.cus; [download]
This works