mysql - 在mysql中将列转置为行

Question

需要帮助配置以下查询:

查询1:

SELECT  @s:= @s + 1 serial_number,`COLUMN_NAME` 
FROM  `INFORMATION_SCHEMA`.`COLUMNS`, (SELECT @s:= 0) AS s 
WHERE `TABLE_SCHEMA`='2014rawfiles' 
AND `TABLE_NAME`='012014actives';

查询1输出:

|  serial_number  |  COLUMN_NAME  |
|        1        |      ID       |
|        2        |   FirstName   |
|        3        |   LastName    |
   ... up to 89 rows ...

我正在尝试将此查询的输出转置为如下所示:

|  1  |      2      |     3     |
| ID  |  FirstName  | LastName  |

将序列号作为标题，将 COLUMN_NAME 作为单行。有什么想法吗？

提前致谢!

Answer 1

如果你确实需要这个，你可以使用动态 SQL 来实现

SET @sql = NULL;

SELECT GROUP_CONCAT(CONCAT('''',column_name, ''' `', @n := @n + 1, '`'))
  INTO @sql
  FROM information_schema.columns CROSS JOIN (SELECT @n := 0) i
 WHERE table_schema = SCHEMA()
   AND table_name = '012014actives'
 ORDER BY ordinal_position;    

SET @sql = CONCAT('SELECT ', @sql);

PREPARE stmt FROM @sql;
EXECUTE stmt;
DEALLOCATE PREPARE stmt;

输出:

|  1 |         2 |        3 |
|----|-----------|----------|
| Id | FirstName | LastName |

这是一个 SQLFiddle 演示