具有两个输入值的 sql server 中的 UNPIVOT（从 Oracle 转换为 sql server）

Question

在 Oracle 中，我写了一个使用 UNPIVOT 的语句。那部分看起来像这样：

''' unpivot ((value, prev_value) for col in ( (title, prev_title) as 'title' , (stage, prev_stage) as 'stage' , (value, prev_value) as 'value' '''

到目前为止，我无法找到一种对 sql server 执行相同操作的方法。任何建议l

Answer 1

使用UNION ALL：

SELECT other_column1,
       other_column2,
       'title' AS col,
       title AS value,
       prev_title AS prev_value
FROM   table_name
WHERE  title IS NOT NULL
AND    prev_title IS NOT NULL
UNION ALL
SELECT other_column1,
       other_column2,
       'stage' AS col,
       stage AS value,
       prev_stage AS prev_value
FROM   table_name
WHERE  stage IS NOT NULL
AND    prev_stage IS NOT NULL
UNION ALL
SELECT other_column1,
       other_column2,
       'value' AS col,
       value,
       prev_value
FROM   table_name
WHERE  value IS NOT NULL
AND    prev_value IS NOT NULL

fiddle