select d.*,case when (d.同期增长值*1.00/d.'2020当月销量'*1.00) is null then 0 else (d.同期增长值*1.00/d.'2020当月销量'*1.00) end 同比 from (select c.yearmonth '2020年月',c.saleamount '2020当月销量',b.yearmonth '2021年月',b.saleamount '2021当月销量',b.saleamount - c.saleamount 同期增长值 from(select * from (select a.*,substr(a.yearmonth,0,5) year,substr(a.yearmonth,6,2) month from sql2003 ajoin (select *,substr(yearmonth,0,5) year,substr(yearmonth,6,2) month from sql2003) b on a.yearmonth = b.yearmonth)where year = '2020') cjoin(select * from (select a.*,substr(a.yearmonth,0,5) year,substr(a.yearmonth,6,2) month from sql2003 ajoin (select *,substr(yearmonth,0,5) year,substr(yearmonth,6,2) month from sql2003) b on a.yearmonth = b.yearmonth)where year = '2021') b where b.month = c.month) d order by d.'2020年月'
