[英]Combining multiple SQL queries of same type in a single result set in PostgreSQL
[英]PostgreSQL - Combining result-rows from multiple queries
我很难将来自同一table.column的两个列加在一起,并具有两个不同的值。
如何将以下两个查询加在一起,以给出两个各自具有各自值的新列;
SELECT
... more columns ...
components.description,
FROM
...
WHERE
graphiccards.id = systems.id AND
components.id = graphiccards.component_id;
SELECT
components.description
FROM
...
WHERE
components.id = mainboards.component_id AND
mainboards.id = systems.mainboard_id
我希望这两个结果在两个不同列的同一行中。
您可能希望看一下UNION
运算符
select
components.description
stuff as second_column
from mytable where conditions
union
select
components.description
stuff2 as second_column
from mytable2 where conditions2
您只需要确保具有相同名称的相同nr列即可。
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.