Question

我的数据包含下表：

t1 (results):    card_id     group_id    project_id    user_id

包含实际标签的表格为：

t2 (groups):    id    project_id    label

t3 (cards):     id    project_id    label

不同的用户可能会有多个条目。

我需要帮助编写查询以表格格式显示结果，总计数对应卡片/组。这是我的开始，但我不确定我是否在正确的轨道上......

SELECT COUNT(card_id) AS cTotal, COUNT(group_id) AS gTotal
WHERE project_id = $projID

Answer 1

如果您知道有九个组的固定事实，那么只需在子查询中包含这些组 - 与此类似：

select cTotal, g1.gTotal as Group1, g2.gTotal as Group2... etc
from
( SELECT COUNT(card_id) AS cTotal
, COUNT(group_id) AS gTotal
WHERE project_id = $projID
AND group_id = 1 ) g1
, ( SELECT COUNT(card_id) AS cTotal
, COUNT(group_id) AS gTotal
WHERE project_id = $projID
AND group_id = 2 ) g2
etc.

Answer 2

除非我弄错了，否则您需要做的就是给出给定project_id的card_id和group_id分组，并为每个组提取计数

SELECT card_id, group_id, COUNT(user_id) FROM mytable 
WHERE project_id = 001
GROUP BY (card_id, group_id);

修改

考虑到卡和组表涉及一些连接，但查询基本相同。仍然按卡和组进行分组，并按项目ID进行约束

SELECT c.label, g.label, COUNT(t1.user_id) FROM mytable t1 JOIN groups g ON t1.group_id=g.id JOIN cards c ON t1.card_is=c.id WHERE t1.project_id = 001 GROUP BY (c.card_id, g.group_id) ORDER BY (c.card_id, g.group_id);

我认为你不能只用SQL获得一个表。您必须通过迭代结果来在代码中呈现表。如何操作取决于您使用的语言/平台。

使用MySQL组织数据输出

2 个答案: