Implementation of mysql Row Column Dynamic Conversion of Column Table Crosstab

(1) Dynamic, applicable to column uncertainty

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) Use when the second field is determined

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;

Note: WITH ROLLUP is used for column summation;SUM (col2='total', col3,0)) AS total is used for on-line summation.

(3) Use when the second field is determined

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 ;