1
select yearmonth,
sum(saleamount) saleamount,
avg(saleamount / saleqty) unitprice
from t_sale
where pname = '空è°'
group by yearmonth
order by yearmonth
2
select pname,
sum(case when substr(yearmonth,1,4)='2016' then saleqty else 0 end) "2016",
sum(case when substr(yearmonth,1,4)='2017' then saleqty else 0 end) "2017",
sum(case when substr(yearmonth,1,4)='2018' then saleqty else 0 end) "2018"
from t_sale group by pname