旋转SQL表

Question

我编写了一个返回下表的SQL查询，该表有3列。每个值都是一个百分比。

A列-B栏-C列

.1 .6 .3

如何旋转此表以便我有两列和三行：一列用于名称，第二列用于值？我希望结果看起来像

列-A。

专栏-B

专栏-C.3

以下是我使用的查询：

SELECT percent(SUM (CASE WHEN fups.status = 'complete' THEN 1 ELSE 0 END),
    COUNT(fups.*)) AS "Column A",
    percent(SUM (CASE WHEN fups.status = 'open' THEN 1 ELSE 0 END),
    COUNT(fups.*)) AS "Column B",
    percent(SUM (CASE WHEN fups.status = 'dismissed' THEN 1 ELSE 0 END),
    COUNT(fups.*)) AS "Column C"
FROM ( 
    SELECT * 
    FROM tasks
    WHERE task_type = 'new'
) fups

Answer 1

使用案例生成名称部分，然后按其分组并使用计数：

SELECT
    CASE status
        WHEN 'complete' THEN 'Column A'
        WHEN 'open' THEN 'Column B'
        WHEN 'dismissed' THEN 'Column C'
    END name,
    percent(COUNT(*), (SELECT COUNT(*) FROM tasks
        WHERE task_type = 'new'
        AND status IN ('completed', 'open', 'dismissed')) "percent"
FROM tasks
WHERE task_type = 'new'
AND status IN ('completed', 'open', 'dismissed')
GROUP BY CASE status
        WHEN 'complete' THEN 'Column A'
        WHEN 'open' THEN 'Column B'
        WHEN 'dismissed' THEN 'Column C'
    END

虽然为什么你不会简单地使用状态列的值来逃避我。

此外，如果您可以指出您正在使用的确切数据库，则可以采用更有效的方式对其进行编码。