sql - Oracle:转置表

Question

我有以下查询

SELECT 1, 2 FROM DUAL

我想要类似的东西

SELECT TRANSPOSE(SELECT 1, 2 FROM DUAL)

哪个输出与

SELECT 1 FROM DUAL
UNION
SELECT 2 FROM DUAL

我希望它用列交换行。

Answer 1

假设这是 Oracle 11，您可以使用 UNPIVOT:

select no from
(SELECT 1 a, 2 b FROM DUAL) dummy
unpivot (no for col in (a as 'A', b as 'B'))