在PostgreSQL中将2个视图合并为一个 [英] Combining 2 views into one in PostgreSQL

问题描述

我需要做些完全疯狂的事情。我有2个具有相同列数的视图（虽然ID列除外，但列名不同），而且它们都碰巧有
2个现有的UNION查询。据我了解， UNION 和 UNION ALL 仅在结合2个 SELECT 查询，在这里我试图结合其中的4个！又就是2个视图。

I need to do something completely insane. I have 2 views that have the same number of columns (different column names though except the ID column) and they both happen to have 2 existing UNION queries. From my understanding UNION and UNION ALL only work when combining 2 SELECT queries, here I'm trying to combine 4 of them! Aka the 2 views.

推荐答案

据我了解，UNION和UNION ALL仅在组合2个SELECT查询时才起作用

"from my understanding UNION and UNION ALL only work when combining 2 SELECT Queries"

Ummmm ... no 。您可以执行以下操作：

Ummmm...no. You can do something like the following:

select col1,col2
from table
union all
select col1,col2
from some_other_table
union all
select col1,col2
from yet_another_table;

等，等等。

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