Question

我使用breezingform为joomla创建web表单，它将用户输入记录存储在数据库中，如下所示：

forms_records

id  | form  | name          
24    19       kpi          
25    19       kpi

forms_subrecords

id   | element  | record    | description  |  value  | type
101     406        24          month         2015-01   calendar
102     407        24          east          30%       text
103     408        24          south         35%       text
104     409        24          north         50%       text
105     410        24          west          25%       text
106     406        25          month         2015-02   calendar
107     407        25          east          45%       text
108     408        25          south         35%       text
109     409        25          north         15%       text
110     410        25          west          5%        text

我试过这样做： 1.首先获得记录ID

SELECT id FROM forms_records WHERE form='19'

获取子记录值

SELECT s.value 
from forms_subrecords AS s 
WHERE s.record 
  IN (SELECT id FROM forms_records WHERE form='19')

结果是10行，一列，

2015-01
30%
35%
50%
25%
2015-02
45%
35%
15%
5%

但我想要的是2行5列：

2015-01 30% 35% 50% 25% 
2015-02 45% 35% 15% 5%

任何人都可以提供帮助或提供一些提示吗？

Answer 1

也许Pivot会起作用。希望能帮助到你。 http://en.wikibooks.org/wiki/MySQL/Pivot_table

Answer 2

您可以将条件案例表达式与聚合最大函数一起使用来执行此操作：

SELECT 
  max(case when s.description = 'month' then s.value end) col1,
  max(case when s.description = 'east'  then s.value end) col2,
  max(case when s.description = 'south' then s.value end) col3,
  max(case when s.description = 'north' then s.value end) col4,
  max(case when s.description = 'west'  then s.value end) col5
FROM forms_subrecords AS s 
WHERE s.record 
  IN (SELECT id FROM forms_records WHERE form='19')
GROUP BY 
  record

示例SQL Fiddle提供此输出：

|    COL1 | COL2 | COL3 | COL4 | COL5 |
|---------|------|------|------|------|
| 2015-01 |  30% |  35% |  50% |  25% |
| 2015-02 |  45% |  35% |  15% |   5% |

如何查询mysql记录在一列中存储值

2 个答案: