Question

我的表格看起来像这样：

r01 r02 r03 r04
1   2   X   X
1   2   X   1
X   1   2   1
X   2   2   2
1   2   1   X
1   1   1   2
1   X   1   1
1   2   X   1
2   2   X   2

我想为每个列（不是行）获取频率数组列表，类似于array_count_values()。像

r01: 1 => 6, X => 2, 2 => 1
r02: 1 => 2, X => 1, 2 => 6
r03: 1 => 3, X => 4, 2 => 2
r04: 1 => 4, X => 2, 2 => 3

是否可以使用一个或几个mysql问题？我没有提出想法。我唯一的解决方案是将所有数据都提供给PHP然后拥有一个数据数组，然后只为每一行的相应计数器添加一个数据。

我可以有100-> 20000行。所以我想有一个比PHP解决方案更好扩展的mysql解决方案。

- 编辑

我正在显示一个简化的表格结构，但我想我需要显示完整的表格。

CREATE TABLE IF NOT EXISTS `tips_rows` (
  `row_id` int(11) NOT NULL,
  `r01` enum('1','X','2') NOT NULL,
  `r02` enum('1','X','2') NOT NULL,
  `r03` enum('1','X','2') NOT NULL,
  `r04` enum('1','X','2') NOT NULL,
  `r05` enum('1','X','2') NOT NULL,
  `r06` enum('1','X','2') NOT NULL,
  `r07` enum('1','X','2') NOT NULL,
  `r08` enum('1','X','2') NOT NULL,
  `r09` enum('1','X','2') NOT NULL,
  `r10` enum('1','X','2') NOT NULL,
  `r11` enum('1','X','2') NOT NULL,
  `r12` enum('1','X','2') NOT NULL,
  `r13` enum('1','X','2') NOT NULL,
  PRIMARY KEY (`row_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

并且tips_rows包含值的所有组合。（1,600万行）对此我有一个链接表连接用户到tips_rows，'tps_rows_users'

因此，对于每个用户，此链接表将为多个用户保存100-10000 row_id的数据集。

我找到了一个基于其他stackoverflow谷歌搜索的解决方案。也许不是最纯粹的查询，但它的工作原理很快。

 SELECT
    SUM(CASE WHEN r01 = '1' THEN 1 ELSE 0 END) AS r11,
    SUM(CASE WHEN r01 = 'X' THEN 1 ELSE 0 END) AS r1X,
    SUM(CASE WHEN r01 = '2' THEN 1 ELSE 0 END) AS r12,
    SUM(CASE WHEN r02 = '1' THEN 1 ELSE 0 END) AS r21,
    SUM(CASE WHEN r02 = 'X' THEN 1 ELSE 0 END) AS r2X,
    SUM(CASE WHEN r02 = '2' THEN 1 ELSE 0 END) AS r22,
    SUM(CASE WHEN r03 = '1' THEN 1 ELSE 0 END) AS r31,
    SUM(CASE WHEN r03 = 'X' THEN 1 ELSE 0 END) AS r3X,
    SUM(CASE WHEN r03 = '2' THEN 1 ELSE 0 END) AS r32,
    SUM(CASE WHEN r04 = '1' THEN 1 ELSE 0 END) AS r41,
    SUM(CASE WHEN r04 = 'X' THEN 1 ELSE 0 END) AS r4X,
    SUM(CASE WHEN r04 = '2' THEN 1 ELSE 0 END) AS r42,
    SUM(CASE WHEN r05 = '1' THEN 1 ELSE 0 END) AS r51,
    SUM(CASE WHEN r05 = 'X' THEN 1 ELSE 0 END) AS r5X,
    SUM(CASE WHEN r05 = '2' THEN 1 ELSE 0 END) AS r52,
    SUM(CASE WHEN r06 = '1' THEN 1 ELSE 0 END) AS r61,
    SUM(CASE WHEN r06 = 'X' THEN 1 ELSE 0 END) AS r6X,
    SUM(CASE WHEN r06 = '2' THEN 1 ELSE 0 END) AS r62,
    SUM(CASE WHEN r07 = '1' THEN 1 ELSE 0 END) AS r71,
    SUM(CASE WHEN r07 = 'X' THEN 1 ELSE 0 END) AS r7X,
    SUM(CASE WHEN r07 = '2' THEN 1 ELSE 0 END) AS r72,
    SUM(CASE WHEN r08 = '1' THEN 1 ELSE 0 END) AS r81,
    SUM(CASE WHEN r08 = 'X' THEN 1 ELSE 0 END) AS r8X,
    SUM(CASE WHEN r08 = '2' THEN 1 ELSE 0 END) AS r82,
    SUM(CASE WHEN r09 = '1' THEN 1 ELSE 0 END) AS r91,
    SUM(CASE WHEN r09 = 'X' THEN 1 ELSE 0 END) AS r9X,
    SUM(CASE WHEN r09 = '2' THEN 1 ELSE 0 END) AS r92,
    SUM(CASE WHEN r10 = '1' THEN 1 ELSE 0 END) AS r101,
    SUM(CASE WHEN r10 = 'X' THEN 1 ELSE 0 END) AS r10X,
    SUM(CASE WHEN r10 = '2' THEN 1 ELSE 0 END) AS r102,
    SUM(CASE WHEN r11 = '1' THEN 1 ELSE 0 END) AS r111,
    SUM(CASE WHEN r11 = 'X' THEN 1 ELSE 0 END) AS r11X,
    SUM(CASE WHEN r11 = '2' THEN 1 ELSE 0 END) AS r112,
    SUM(CASE WHEN r12 = '1' THEN 1 ELSE 0 END) AS r121,
    SUM(CASE WHEN r12 = 'X' THEN 1 ELSE 0 END) AS r12X,
    SUM(CASE WHEN r12 = '2' THEN 1 ELSE 0 END) AS r122,
    SUM(CASE WHEN r13 = '1' THEN 1 ELSE 0 END) AS r131,
    SUM(CASE WHEN r13 = 'X' THEN 1 ELSE 0 END) AS r13X,
    SUM(CASE WHEN r13 = '2' THEN 1 ELSE 0 END) AS r132
    FROM `tips_rows` AS r
    INNER JOIN tips_rows_users USING (row_id)
    WHERE user__id='{userid}'

这将给我一个结果行

r11 r1X r12 r21 r2X r22 r31 r3X r32 r41 r4X r42 r51 r5X r52 r61 r6X r62 r71 r7X r72 r81 r8X r82 r91 r9X r92 r101 r10X r102 r111 r11X r112 r121 r12X r122 r131 r13X r132
40  34  26  48  30  22  69  14  17  70  16  14  15  17  68  28  31  41  80  20  0   49  29  22  38  30  32  69   16   15   29   28   43   19   31   50   13   25   62

我可以在我的php-template文件中使用。

Answer 1

试试这个::

Select 'R01', r01, count(1) from myTable group by r01
UNION 
Select 'R02', r02, count(1) from myTable group by r02 
UNION
Select 'R03', r03, count(1) from myTable group by r03 
UNION
Select 'R04', r04, count(1) from myTable group by r04

Answer 2

假设每列只有4列和3个可能值，并且如果您真的希望结果显示为“每个值一列”：

SELECT 'R01' AS 'Row', SUM(IF(r01 = 1, 1, 0)) as '1',
                       SUM(IF(r01 = 2, 1, 0)) as '2',
                       SUM(IF(r01 = 'X', 1, 0)) as 'X'
       FROM myTable
UNION  SELECT 'R02', SUM(IF(r02 = 1, 1, 0)) as '1',
                       SUM(IF(r02 = 2, 1, 0)) as '2',
                       SUM(IF(r02 = 'X', 1, 0)) as 'X'
       FROM myTable
UNION  SELECT 'R03', SUM(IF(r03 = 1, 1, 0)) as '1',
                       SUM(IF(r03 = 2, 1, 0)) as '2',
                       SUM(IF(r03 = 'X', 1, 0)) as 'X'
       FROM myTable

UNION  SELECT 'R04', SUM(IF(r04 = 1, 1, 0)) as '1',
                       SUM(IF(r04 = 2, 1, 0)) as '2',
                       SUM(IF(r04 = 'X', 1, 0)) as 'X'
       FROM myTable

产：

+------+----+----+---+
| ROW  | 1  | 2  | X |
+------+----+----+---+
| R01  | 6  | 1  | 2 |
| R02  | 2  | 6  | 1 |
| R03  | 3  | 2  | 4 |
| R04  | 4  | 3  | 2 |
+------+----+----+---+

请参阅http://sqlfiddle.com/#!2/c6376/2

如果可以接受旋转结果表，则以下查询将更好地执行更多：

SELECT n,
       SUM(IF(r01 = n, 1, 0)) AS 'r01',
       SUM(IF(r02 = n, 1, 0)) AS 'r02',
       SUM(IF(r03 = n, 1, 0)) AS 'r03',
       SUM(IF(r04 = n, 1, 0)) AS 'r04'
FROM mytable JOIN (SELECT '1' AS n UNION SELECT '2' UNION SELECT 'X') S
GROUP BY n;

导致：

+----+------+------+------+-----+
|    | R01  | R02  | R03  | R04 |
+----+------+------+------+-----+
| 1  |   6  |   2  |   3  |   4 |
| 2  |   1  |   6  |   2  |   3 |
| X  |   2  |   1  |   4  |   2 |
+----+------+------+------+-----+

Answer 3

感谢所有不同的解决方案。我现在已对我的数据进行了一些测试。我已经完成了10000rows的查询。这是我的发现。

解决方案1：

Select 'R01', r01, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r01
UNION 
Select 'R02', r02, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r02 
UNION
Select 'R03', r03, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r03 
UNION
Select 'R04', r04, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r04 
UNION
Select 'R05', r05, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r05 
UNION
Select 'R06', r06, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r06 
UNION
Select 'R07', r07, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r07 
UNION
Select 'R08', r08, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r08 
UNION
Select 'R09', r09, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r09 
UNION
Select 'R10', r10, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r10 
UNION
Select 'R11', r11, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r11 
UNION
Select 'R12', r12, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r12 
UNION
Select 'R13', r13, count(1) FROM `tips_rows` AS r INNER JOIN tips_rows_users USING (row_id) WHERE user_id='27' group by r13

每次查询需要~0.1365s

解决方案2：

SELECT n,
       SUM(IF(r01 = n, 1, 0)) AS 'r01',
       SUM(IF(r02 = n, 1, 0)) AS 'r02',
       SUM(IF(r03 = n, 1, 0)) AS 'r03',
       SUM(IF(r04 = n, 1, 0)) AS 'r04',
       SUM(IF(r05 = n, 1, 0)) AS 'r05',
       SUM(IF(r06 = n, 1, 0)) AS 'r06',
       SUM(IF(r07 = n, 1, 0)) AS 'r07',
       SUM(IF(r08 = n, 1, 0)) AS 'r08',
       SUM(IF(r09 = n, 1, 0)) AS 'r09',
       SUM(IF(r10 = n, 1, 0)) AS 'r10',
       SUM(IF(r11 = n, 1, 0)) AS 'r11',
       SUM(IF(r12 = n, 1, 0)) AS 'r12',
       SUM(IF(r13 = n, 1, 0)) AS 'r13'       
FROM `tips_rows` AS r
INNER JOIN tips_rows_users USING (row_id)
JOIN (SELECT '1' AS n UNION SELECT '2' UNION SELECT 'X') S
WHERE user_id='27'
GROUP BY n;

第一次查询时需要~0.0997s。可以缓存在mysql查询缓存中，因此第二次需要~0.0002s

解决方案3：

SELECT
    SUM(CASE WHEN r01 = '1' THEN 1 ELSE 0 END) AS r11,
    SUM(CASE WHEN r01 = 'X' THEN 1 ELSE 0 END) AS r1X,
    SUM(CASE WHEN r01 = '2' THEN 1 ELSE 0 END) AS r12,
    SUM(CASE WHEN r02 = '1' THEN 1 ELSE 0 END) AS r21,
    SUM(CASE WHEN r02 = 'X' THEN 1 ELSE 0 END) AS r2X,
    SUM(CASE WHEN r02 = '2' THEN 1 ELSE 0 END) AS r22,
    SUM(CASE WHEN r03 = '1' THEN 1 ELSE 0 END) AS r31,
    SUM(CASE WHEN r03 = 'X' THEN 1 ELSE 0 END) AS r3X,
    SUM(CASE WHEN r03 = '2' THEN 1 ELSE 0 END) AS r32,
    SUM(CASE WHEN r04 = '1' THEN 1 ELSE 0 END) AS r41,
    SUM(CASE WHEN r04 = 'X' THEN 1 ELSE 0 END) AS r4X,
    SUM(CASE WHEN r04 = '2' THEN 1 ELSE 0 END) AS r42,
    SUM(CASE WHEN r05 = '1' THEN 1 ELSE 0 END) AS r51,
    SUM(CASE WHEN r05 = 'X' THEN 1 ELSE 0 END) AS r5X,
    SUM(CASE WHEN r05 = '2' THEN 1 ELSE 0 END) AS r52,
    SUM(CASE WHEN r06 = '1' THEN 1 ELSE 0 END) AS r61,
    SUM(CASE WHEN r06 = 'X' THEN 1 ELSE 0 END) AS r6X,
    SUM(CASE WHEN r06 = '2' THEN 1 ELSE 0 END) AS r62,
    SUM(CASE WHEN r07 = '1' THEN 1 ELSE 0 END) AS r71,
    SUM(CASE WHEN r07 = 'X' THEN 1 ELSE 0 END) AS r7X,
    SUM(CASE WHEN r07 = '2' THEN 1 ELSE 0 END) AS r72,
    SUM(CASE WHEN r08 = '1' THEN 1 ELSE 0 END) AS r81,
    SUM(CASE WHEN r08 = 'X' THEN 1 ELSE 0 END) AS r8X,
    SUM(CASE WHEN r08 = '2' THEN 1 ELSE 0 END) AS r82,
    SUM(CASE WHEN r09 = '1' THEN 1 ELSE 0 END) AS r91,
    SUM(CASE WHEN r09 = 'X' THEN 1 ELSE 0 END) AS r9X,
    SUM(CASE WHEN r09 = '2' THEN 1 ELSE 0 END) AS r92,
    SUM(CASE WHEN r10 = '1' THEN 1 ELSE 0 END) AS r101,
    SUM(CASE WHEN r10 = 'X' THEN 1 ELSE 0 END) AS r10X,
    SUM(CASE WHEN r10 = '2' THEN 1 ELSE 0 END) AS r102,
    SUM(CASE WHEN r11 = '1' THEN 1 ELSE 0 END) AS r111,
    SUM(CASE WHEN r11 = 'X' THEN 1 ELSE 0 END) AS r11X,
    SUM(CASE WHEN r11 = '2' THEN 1 ELSE 0 END) AS r112,
    SUM(CASE WHEN r12 = '1' THEN 1 ELSE 0 END) AS r121,
    SUM(CASE WHEN r12 = 'X' THEN 1 ELSE 0 END) AS r12X,
    SUM(CASE WHEN r12 = '2' THEN 1 ELSE 0 END) AS r122,
    SUM(CASE WHEN r13 = '1' THEN 1 ELSE 0 END) AS r131,
    SUM(CASE WHEN r13 = 'X' THEN 1 ELSE 0 END) AS r13X,
    SUM(CASE WHEN r13 = '2' THEN 1 ELSE 0 END) AS r132
    FROM `tips_rows` AS r
    INNER JOIN tips_rows_users USING (row_id)
    WHERE user_id='27'

第一次和第二次需要~0.0587s。之后是0.0002s之后的问题。

我会选择解决方案3.因为它有最好的最坏情况时间。但奇怪的是，它在缓存之前需要两个查询。

表中每列的频率列表

3 个答案: