MySQL/MariaDB 如何实现数据透视表的示例代码

select coalesce(product, '【全部产品】') "产品",
    coalesce(channel, '【所有渠道】') "渠道",
    any_value(coalesce(extract(year_month from saledate), '【所有月份】')) "月份",
    sum(amount) "销量"
from sales_data
group by product,channel,extract(year_month from saledate) with rollup;

select coalesce(product, '【全部产品】') "产品", coalesce(channel, '【所有渠道】') "渠道", 
    sum(case extract(year_month from saledate) when 201901 then amount else 0 end) "一月",
    sum(case extract(year_month from saledate) when 201902 then amount else 0 end) "二月",
    sum(case extract(year_month from saledate) when 201903 then amount else 0 end) "三月",
    sum(case extract(year_month from saledate) when 201904 then amount else 0 end) "四月",
    sum(case extract(year_month from saledate) when 201905 then amount else 0 end) "五月",
    sum(case extract(year_month from saledate) when 201906 then amount else 0 end) "六月",
    sum(amount) "总计"
from sales_data
group by product, channel with rollup;

with d as (
 select product, channel,
     sum(case extract(year_month from saledate) when 201901 then amount else 0 end) s01,
     sum(case extract(year_month from saledate) when 201902 then amount else 0 end) s02,
     sum(case extract(year_month from saledate) when 201903 then amount else 0 end) s03,
     sum(case extract(year_month from saledate) when 201904 then amount else 0 end) s04,
     sum(case extract(year_month from saledate) when 201905 then amount else 0 end) s05,
     sum(case extract(year_month from saledate) when 201906 then amount else 0 end) s06
 from sales_data
 group by product, channel
)
select product, channel, 201901 saledate, s01 amount from d
union all
select product, channel, 201902 saledate, s02 from d
union all
select product, channel, 201903 saledate, s03 from d
union all
select product, channel, 201904 saledate, s04 from d
union all
select product, channel, 201905 saledate, s05 from d
union all
select product, channel, 201906 saledate, s06 from d;

select group_concat(
 distinct concat(
  ' sum(case extract(year_month from saledate) when ', dt,
  ' then amount else 0 end) as "', dt, '"')
 ) into @sql
from (
 select extract(year_month from saledate) as dt
 from sales_data
 order by saledate
) d;

set @sql
 = concat('select coalesce(product, ''【全部产品】'') "产品", coalesce(channel, ''【所有渠道】'') "渠道",', @sql,
      ', sum(amount) "总计"
      from sales_data
      group by product, channel with rollup;');
select @sql;
prepare stmt from @sql;
execute stmt;
deallocate prepare stmt;

select coalesce(product, '【全部产品】') "产品", coalesce(channel, '【所有渠道】') "渠道", 
    sum(case extract(year_month from saledate) when 201901 then amount else 0 end) as "201901", 
    sum(case extract(year_month from saledate) when 201902 then amount else 0 end) as "201902", 
    sum(case extract(year_month from saledate) when 201903 then amount else 0 end) as "201903", 
    sum(case extract(year_month from saledate) when 201904 then amount else 0 end) as "201904", 
    sum(case extract(year_month from saledate) when 201905 then amount else 0 end) as "201905", 
    sum(case extract(year_month from saledate) when 201906 then amount else 0 end) as "201906", 
    sum(amount) "总计"
from sales_data
group by product, channel with rollup;

INSTALL SONAME 'ha_connect';

[mysqld]
plugin_load_add = ha_connect

create table pivot_sales(
 product varchar(20) not null,
 channel varchar(20) not null,
 `201901` decimal(10,2) not null flag=1,
 `201902` decimal(10,2) not null flag=1,
 `201903` decimal(10,2) not null flag=1,
 `201904` decimal(10,2) not null flag=1,
 `201905` decimal(10,2) not null flag=1,
 `201906` decimal(10,2) not null flag=1
)
engine=connect table_type=pivot
option_list='PivotCol=saledate,FncCol=amount,host=127.0.0.1,user=root, password=p123456,port=3306'
SrcDef='select product,channel,date_format(saledate, ''%Y%m'') saledate,sum(amount) amount from sales_data group by product,channel,date_format(saledate, ''%Y%m'')';

select * from pivot_sales;

product |channel |201901 |201902 |201903 |201904 |201905 |201906 |
--------|---------|--------|--------|--------|--------|--------|--------|
桔子   |京东   |41289.00|43913.00|49803.00|49256.00|64889.00|62649.00|
桔子   |店面   |41306.00|37906.00|48866.00|48673.00|58998.00|58931.00|
桔子   |淘宝   |43488.00|37598.00|48621.00|49919.00|58530.00|64626.00|
苹果   |京东   |38269.00|40593.00|56552.00|56662.00|64493.00|62045.00|
苹果   |店面   |43845.00|40539.00|44909.00|55646.00|56771.00|64933.00|
苹果   |淘宝   |42969.00|43289.00|48769.00|58052.00|58872.00|59844.00|
香蕉   |京东   |36879.00|36981.00|51748.00|54801.00|64936.00|60688.00|
香蕉   |店面   |41210.00|39420.00|50884.00|52085.00|60249.00|67597.00|
香蕉   |淘宝   |42468.00|41955.00|52780.00|54971.00|56504.00|59213.00|

-- 不会出错
select * from pivot_sales
where channel ='京东';

-- 语法错误
select channel from pivot_sales
where channel ='京东';