所以我试图用SQL查询创建一个数据透视表。目前我正在以片材方式进行此过程，但希望减少痛苦。
ip domain type date provider type_of_event number_of_events
999 mail.com normal 2018-08-31 orange abuse 12
999 mail1.com normal 2018-08-30 orange abuse 11
999 mail1.com normal 2018-08-29 orange abuse 13
999 mail.com normal 2018-08-31 orange abuse 10
而且我希望它是这样的
Domain 2018-08-29 2018-08-30 2018-08-31 Grand Total
mail.com 22 22
mail1.com 13 11 24
我遇到了格式化的问题，因为我发现的大多数示例都有固定字段，然后日期总是会改变，但我需要它来显示正在处理的当前字段。这将始终以3天为增量。我需要它也引用type_of_event，因为示例只显示一种类型，但我在同一个数据库中有多个。
这个问题与其他问题不同，因为我没有这个数据来自的多个表。所有这些数据都在一个表中。当我没有任何东西可以加入时，我不知道枢轴连接会如何帮助？
所以使用这个
SELECT CONCAT('SELECT
domain,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 3 DAY))
AS `', CURRENT_DATE() - INTERVAL 3 DAY, '`,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 2 DAY))
AS `', CURRENT_DATE() - INTERVAL 2 DAY, '`,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 1 DAY))
AS `', CURRENT_DATE() - INTERVAL 1 DAY, '`,
SUM(number_of_events) AS `Grand Total`
FROM signal_spam
GROUP BY domain;'
) AS theQuery;
给我
+----------------------------------------------------------------------------
-----------------------------------------------------------------------------
-
-----------------------------------------------------------------------------
-
-----------------------------------------------------------------------------
-
-----------------------------------------------------------------------------
-
----------------+
| theQuery
|
+----------------------------------------------------------------------------
-----------------------------------------------------------------------------
-
------------------------------------------------------------------------------
------------------------------------------------------------------------------
------------------------------------------------------------------------------
----------------+
| SELECT
domain,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 3 DAY))
AS `2018-09-11`,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 2 DAY))
AS `2018-09-12`,
SUM(number_of_events * (date_of_event = CURRENT_DATE() - INTERVAL 1 DAY))
AS `2018-09-13`,
SUM(number_of_events) AS `Grand Total`
FROM signal_spam
GROUP BY domain; |
+----------------------------------------------------------------------------
-----------------------------------------------------------------------------
-
----------------------------------------------------------------------------
--
-----------------------------------------------------------------------------
-
-----------------------------------------------------------------------------
-
----------------+
1 row in set (0.00 sec)
如果我删除concat我在行中没有计数只是总计，也没有列出日期
+------------------------------------+---------------------------------------
+---------------------------------------+------------------------------------
-
--+-------------+
| domain | ', CURRENT_DATE() - INTERVAL 3 DAY, '
|
', CURRENT_DATE() - INTERVAL 2 DAY, ' | ', CURRENT_DATE() - INTERVAL 1 DAY, '
| Grand Total |
+------------------------------------+---------------------------------------
+---------------------------------------+------------------------------------
-
--+-------------+
| 0.pool. | 0
|
0 | 0 | 258 |
| 143.com | 0
|
0 | 0 | 2 |
MySQL中的动态数据透视表通常通过编写查询来完成，然后生成一串SQL。
SELECT CONCAT('
SELECT
domain,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 3 DAY))
AS `', CURRENT_DATE() - INTERVAL 3 DAY, '`,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 2 DAY))
AS `', CURRENT_DATE() - INTERVAL 2 DAY, '`,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 1 DAY))
AS `', CURRENT_DATE() - INTERVAL 1 DAY, '`,
SUM(number_of_events) AS `Grand Total`
FROM tableName
GROUP BY domain;'
) AS theQuery;
获取该查询的结果，并将其发送回MySQL。
例如，今天运行该查询会产生：
SELECT
domain,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 3 DAY))
AS `2018-09-11`,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 2 DAY))
AS `2018-09-12`,
SUM(number_of_events * (date = CURRENT_DATE() - INTERVAL 1 DAY))
AS `2018-09-13`,
SUM(number_of_events) AS `Grand Total`
FROM signal_spam
GROUP BY domain;
有一个由MySQL动态生成的数据透视表查询。现在只需将该查询复制/粘贴回客户端，最终结果如下：
+-----------+------------+------------+------------+-------------+
| domain | 2018-09-11 | 2018-09-12 | 2018-09-13 | Grand Total |
+-----------+------------+------------+------------+-------------+
| mail.com | 0 | 0 | 22 | 22 |
| mail1.com | 13 | 11 | 0 | 24 |
+-----------+------------+------------+------------+-------------+