CREATE TABLE product  (
  `產(chǎn)品ID` varchar(20) NOT NULL,
	  `產(chǎn)品名稱` varchar(20) ,
  `產(chǎn)品單價` int (10)
)
INSERT INTO product VALUES ('C1001','產(chǎn)品A',45);
INSERT INTO product VALUES ('C1002','產(chǎn)品B',52);
INSERT INTO product VALUES ('C1003','產(chǎn)品C',39);

創(chuàng)建訂單明細表并向訂單明細表中添加數(shù)據(jù)

CREATE TABLE sales  (
    `訂單ID` int NOT NULL PRIMARY KEY AUTO_INCREMENT,
  `產(chǎn)品ID` varchar(25) NOT NULL ,
	  `銷售數(shù)量` int(20) ,
  `銷售時間` timestamp(6) NULL DEFAULT NULL
);
INSERT INTO sales(`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1001', 15, '2020-06-01 10:10:12');
INSERT INTO sales(`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`)  VALUES ('C1002',26, '2020-05-02 0:10:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1003', 21, '2020-04-03 0:10:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1003', 23, '2020-04-04 0:10:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1003', 0, '2020-03-05 0:10:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1001', 16, '2020-02-06 3:0:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1002', 32, '2020-01-07 0:10:12');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1001', 16, '2019-12-08 0:12:24');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1001', 32, '2019-06-09  0:12:24');
INSERT INTO sales (`產(chǎn)品ID`,`銷售數(shù)量`,`銷售時間`) VALUES ('C1002', 17, '2019-05-09 0:12:24');

計算同比和環(huán)比

select  year(c.銷售時間) yy,month(c.銷售時間) mm,     
       sum(c.銷售數(shù)量*d.產(chǎn)品單價) ss,
concat(ifnull(abs(round((sum(c.銷售數(shù)量*d.產(chǎn)品單價)-ss1)/ss1*100,2)),0),'%') 同比,
concat(ifnull(abs(round((sum(c.銷售數(shù)量*d.產(chǎn)品單價)-ss2)/ss2*100,2)),0),'%')  環(huán)比
from sales c
left join product d on c.產(chǎn)品ID=d.產(chǎn)品ID
left join (select month(a.銷售時間) mm1,
                    year(a.銷售時間) yy1,
                    sum(a.銷售數(shù)量*d.產(chǎn)品單價) ss1
          from sales a
          left join product d on a.產(chǎn)品ID=d.產(chǎn)品ID
          GROUP BY mm1,yy1) a
          on month(c.銷售時間) = a.mm1 
          and a.yy1 = year(c.銷售時間)-1	 
 left join  (select month(a.銷售時間) mm2,
                    year(a.銷售時間) yy2,
                    sum(a.銷售數(shù)量*d.產(chǎn)品單價) ss2
             from sales a
		     left join product d on a.產(chǎn)品ID=d.產(chǎn)品ID
              GROUP BY mm2,yy2) b
on (b.yy2 = year(c.銷售時間) and b.mm2+1 = month(c.銷售時間) OR (yy2=year(c.銷售時間)-1 
AND b.mm2 = 12 AND month(c.銷售時間) = 1))
 group by yy, mm
 order by yy,mm asc

sql解析

select  year(c.銷售時間) yy,month(c.銷售時間) mm,     
       sum(c.銷售數(shù)量*d.產(chǎn)品單價) ss,
 
# concat函數(shù)，mysql字符串拼接，因為同比和環(huán)比都是百分數(shù)
# ifnull函數(shù)，mysql判斷字段是否為空，為空則為0
# abs函數(shù),mysql取絕對值，因為我這里取的都是正數(shù)
# round函數(shù)，mysql保留幾位小數(shù)
concat(ifnull(abs(round((sum(c.銷售數(shù)量*d.產(chǎn)品單價)-ss1)/ss1*100,2)),0),'%') 同比,
concat(ifnull(abs(round((sum(c.銷售數(shù)量*d.產(chǎn)品單價)-ss2)/ss2*100,2)),0),'%')  環(huán)比
from sales c
left join product d on c.產(chǎn)品ID=d.產(chǎn)品ID
 
# 上一年銷售額
left join (select month(a.銷售時間) mm1,
                    year(a.銷售時間) yy1,
                    sum(a.銷售數(shù)量*d.產(chǎn)品單價) ss1
          from sales a
          left join product d on a.產(chǎn)品ID=d.產(chǎn)品ID
          GROUP BY mm1,yy1) a
          # 同比月份相同，年份減1
          on month(c.銷售時間) = a.mm1   
          and a.yy1 = year(c.銷售時間)-1	
 
# 今年銷售額 
 left join  (select month(a.銷售時間) mm2,
                    year(a.銷售時間) yy2,
                    sum(a.銷售數(shù)量*d.產(chǎn)品單價) ss2
             from sales a
		     left join product d on a.產(chǎn)品ID=d.產(chǎn)品ID
              GROUP BY mm2,yy2) b
          # 環(huán)比取數(shù)考慮到為一月的情況
on (b.yy2 = year(c.銷售時間) and b.mm2+1 = month(c.銷售時間) OR (yy2=year(c.銷售時間)-1 
AND b.mm2 = 12 AND month(c.銷售時間) = 1))
 group by yy, mm
 order by yy,mm asc

結(jié)果：

除此之外，還想要計算累計銷售的話，可以這樣寫：

select year(銷售時間) yy,month(銷售時間) mm,
sum(銷售數(shù)量*b.產(chǎn)品單價) over(order by year(銷售時間) ,month(銷售時間) ) 累計數(shù)量 
from sales a
left join product b on a.產(chǎn)品ID=b.產(chǎn)品ID
order by  yy,mm

同比和環(huán)比這塊的確不好計算