mysql交叉表查询解决方案整理

交叉表是一种常用的分类汇总查询。使用交叉表查询，可以显示表中某个字段的汇总值，并将它们分组，其中一组列在数据表的左侧，另一组列在数据表的上部。行和列的交叉处可以对数据进行多种汇总计算，如：求和、平均值、记数、最大值、最小值等。使用交叉表查询数据非常直观明了，被广泛应用。交叉表查询也是数据库的一个特点。

以下例子收集自csdn整理

数据样本：
create table tx(
id int primary key,
c1 char(2),
c2 char(2),
c3 int
);

insert into tx 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);

方法一：

mysql> SELECT
    ->     IFNULL(c1,'total') AS total,
    ->     SUM(IF(c2='B1',c3,0)) AS B1,
    ->     SUM(IF(c2='B2',c3,0)) AS B2,
    ->     SUM(IF(c2='B3',c3,0)) AS B3,
    ->     SUM(IF(c2='B4',c3,0)) AS B4,
    ->     SUM(IF(c2='total',c3,0)) AS total
    -> FROM (
    ->     SELECT c1,IFNULL(c2,'total') AS c2,SUM(c3) AS c3
    ->     FROM tx
    ->     GROUP BY c1,c2
    ->     WITH ROLLUP
    ->     HAVING c1 IS NOT NULL
    -> ) AS A
    -> GROUP BY c1
    -> WITH ROLLUP;
+-------+------+------+------+------+-------+
| total | 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 |
+-------+------+------+------+------+-------+
5 rows in set, 1 warning (0.00 sec)

方法二：

mysql> select c1,
    -> sum(if(c2='B1',C3,0)) AS B1,
    -> sum(if(c2='B2',C3,0)) AS B2,
    -> sum(if(c2='B3',C3,0)) AS B3,
    -> sum(if(c2='B4',C3,0)) AS B4,SUM(C3) AS TOTAL
    -> from tx
    -> group by C1
    -> UNION
    -> SELECT 'TOTAL',sum(if(c2='B1',C3,0)) AS B1,
    -> sum(if(c2='B2',C3,0)) AS B2,
    -> sum(if(c2='B3',C3,0)) AS B3,
    -> sum(if(c2='B4',C3,0)) AS B4,SUM(C3) FROM TX
    -> ;
+-------+------+------+------+------+-------+
| c1    | 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 |
+-------+------+------+------+------+-------+
5 rows in set (0.00 sec)

mysql>

方法三：

mysql> select ifnull(c1,'total'),
    -> sum(if(c2='B1',C3,0)) AS B1,
    -> sum(if(c2='B2',C3,0)) AS B2,
    -> sum(if(c2='B3',C3,0)) AS B3,
    -> sum(if(c2='B4',C3,0)) AS B4,SUM(C3) AS TOTAL
    -> from tx
    -> group by C1 with rollup ;
+--------------------+------+------+------+------+-------+
| ifnull(c1,'total') | 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 |
+--------------------+------+------+------+------+-------+
5 rows in set (0.00 sec)

mysql>