更新时间:2023-02-06 17:48:05
我在 MySQL 8.0.1 上测试了以下内容:
I tested the following on MySQL 8.0.1:
SELECT GROUP_CONCAT(
CONCAT(
'SELECT `Product Type`, ',
QUOTE(COLUMN_NAME), ' AS `Date`, ',
'`', COLUMN_NAME, '` AS `Revenue` ',
'FROM testing_unpivot'
) SEPARATOR ' UNION ALL '
)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'testing_unpivot'
AND COLUMN_NAME <> 'Product Type';
使用QUOTE() 函数 使它更简单,因为它消除了计算三引号和四引号的需要.
Using the QUOTE() function makes it simpler, because it eliminates the need to figure out the triple vs. quad quotes.
输出:
SELECT `Product Type`, '01-31-2016' AS `Date`, `01-31-2016` AS `Revenue` FROM testing_unpivot
UNION ALL
SELECT `Product Type`, '02-29-2016' AS `Date`, `02-29-2016` AS `Revenue` FROM testing_unpivot
UNION ALL
SELECT `Product Type`, '12-31-2015' AS `Date`, `12-31-2015` AS `Revenue` FROM testing_unpivot
然后我做了复制&粘贴以运行该查询并获得此输出:
Then I did copy & paste to run that query and got this output:
+--------------+------------+---------+
| Product Type | Date | Revenue |
+--------------+------------+---------+
| A | 01-31-2016 | 400.00 |
| B | 01-31-2016 | 86.88 |
| C | 01-31-2016 | 400.00 |
| D | 01-31-2016 | 55.00 |
| E | 01-31-2016 | 455.00 |
| A | 02-29-2016 | 55.00 |
| B | 02-29-2016 | 55.00 |
| C | 02-29-2016 | 55.00 |
| D | 02-29-2016 | 11.00 |
| E | 02-29-2016 | 22.00 |
| A | 12-31-2015 | 100.00 |
| B | 12-31-2015 | 0.00 |
| C | 12-31-2015 | 200.00 |
| D | 12-31-2015 | 300.00 |
| E | 12-31-2015 | 400.00 |
+--------------+------------+---------+
我刚刚用前三个日期的数据加载了我的测试数据.
I just loaded my test data with your first three dates worth of data.