(1)动态，适用于列不确定情况

create table table_name(

id int primary key,

col1 char(2),

col2 char(2),

col3 int

);

insert into table_name values

(1 ,'A1','B1',9),

(2 ,'A2','B1',7),

(3 ,'A3','B1',4),

(4 ,'A4','B1',2),

(5 ,'A1','B2',2),

(6 ,'A2','B2',9),

(7 ,'A3','B2',8),

(8 ,'A4','B2',5),

(9 ,'A1','B3',1),

(10 ,'A2','B3',8),

(11 ,'A3','B3',8),

(12 ,'A4','B3',6),

(13 ,'A1','B4',8),

(14 ,'A2','B4',2),

(15 ,'A3','B4',6),

(16 ,'A4','B4',9),

(17 ,'A1','B4',3),

(18 ,'A2','B4',5),

(19 ,'A3','B4',2),

(20 ,'A4','B4',5);

select * from table_name;

+----+------+------+------+

| id | col1 | col2 | col3 |

+----+------+------+------+

| 1 | A1 | B1 | 9 |

| 2 | A2 | B1 | 7 |

| 3 | A3 | B1 | 4 |

| 4 | A4 | B1 | 2 |

| 5 | A1 | B2 | 2 |

| 6 | A2 | B2 | 9 |

| 7 | A3 | B2 | 8 |

| 8 | A4 | B2 | 5 |

| 9 | A1 | B3 | 1 |

| 10 | A2 | B3 | 8 |

| 11 | A3 | B3 | 8 |

| 12 | A4 | B3 | 6 |

| 13 | A1 | B4 | 8 |

| 14 | A2 | B4 | 2 |

| 15 | A3 | B4 | 6 |

| 16 | A4 | B4 | 9 |

| 17 | A1 | B4 | 3 |

| 18 | A2 | B4 | 5 |

| 19 | A3 | B4 | 2 |

| 20 | A4 | B4 | 5 |

+----+------+------+------+

SET @EE='';

SELECT @EE:=CONCAT(@EE,'SUM(IF(col2=\'',col2,'\'',',col3,0)) AS ',col2,',') FROM (SELECT DISTINCT col2 FROM table_name) A;

SET @QQ=CONCAT('SELECT ifnull(col1,\'total\') AS columnA,',LEFT(@EE,LENGTH(@EE)-1),' ,SUM(col3) AS TOTAL FROM table_name GROUP BY col1 WITH ROLLUP');

PREPARE stmt2 FROM @QQ;

EXECUTE stmt2;

+---------+------+------+------+------+-------+

| columnA | B1 | B2 | B3 | B4 | TOTAL |

+---------+------+------+------+------+-------+

| A1 | 9 | 2 | 1 | 11 | 23 |

| A2 | 7 | 9 | 8 | 7 | 31 |

| A3 | 4 | 8 | 8 | 8 | 28 |

| A4 | 2 | 5 | 6 | 14 | 27 |

| total | 22 | 24 | 23 | 40 | 109 |

+---------+------+------+------+------+-------+

(2)第二个字段确定的情况下使用

SELECT

IFNULL(col1,'total') AS total,

SUM(IF(col2='B1',col3,0)) AS B1,

SUM(IF(col2='B2',col3,0)) AS B2,

SUM(IF(col2='B3',col3,0)) AS B3,

SUM(IF(col2='B4',col3,0)) AS B4,

SUM(IF(col2='total',col3,0)) AS total

FROM (

SELECT col1,IFNULL(col2,'total') AS col2,SUM(col3) AS col3

FROM table_name

GROUP BY col1,col2

WITH ROLLUP

HAVING col1 IS NOT NULL

) AS A

GROUP BY col1

WITH ROLLUP;

注： WITH ROLLUP 用于列上求和； SUM(IF(col2='total',col3,0)) AS total 用于行上求和。

(3)第二个字段确定的情况下使用

select ifnull(col1,'total') AS col1,

sum(if(col2='B1',col3,0)) AS B1,

sum(if(col2='B2',col3,0)) AS B2,

sum(if(col2='B3',col3,0)) AS B3,

sum(if(col2='B4',col3,0)) AS B4,SUM(col3) AS TOTAL

from table_name

group by col1 with rollup ;

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