本文介绍了多个相同名称的SQL选择列的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我有这个查询
select * from alldistros t1 LEFT join origin t2 on t1.name=t2.name LEFT join desktop t3 on t2.name=t3.name LEFT join beginnerdistributions t4 on t3.name=t4.name它加在我所有的桌子上。但是现在,当我要选择名称字段(所有字段都包含在内)时,我无法显示它。当我打电话时它只是空白。而且我会这么想,因为存在多个同名的列。
it add on all my tables. But now when I want to select the name field (which is in all of them) I can't show it. It's just blank when I call it. And I would think so since there's more than 1 columns of the same name.
我该怎么办才能解决此问题?
What can I do to fix this?
纯联接将不起作用,因为它会删除其他表中没有属性的某些字段。
Just a plain join won't work, since it removes some of the fields that does not have the properties in the other tables.
推荐答案您可以使用 AS关键字来命名列。例如:
You can use the 'AS' keyword to name a column. For instance:
select t1.name AS DistroName, t2.name AS OriginName, t3.name AS DesktopName from alldistros t1 LEFT join origin t2 on t1.name=t2.name LEFT join desktop t3 on t2.name=t3.name LEFT join beginnerdistributions t4 on t3.name=t4.name更多推荐
多个相同名称的SQL选择列
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