SQL按不同列选择整个行 [英] SQL Select Entire Row by Distinct Columns

问题描述

我需要一条sql语句，该语句允许我从oracle数据库中选择整行，但可以通过不同的列进行选择.这是一个简化的数据库:

I need an sql statement which will allow me to select an entire row from oracle database, but by distinct columns. Here is a simplified database:

    Project_Num    Title        Category
    0              Project 1    Admin
    0              Project 1    Development
    1              Project 2    Admin
    2              Project 3    Development

我需要我的语句返回以下结果集:

I need my statement to return the following result set:

0     Project 1    Admin
1     Project 2    Admin
2     Project 3    Development

因此，将根据每个项目的project_num和title是否唯一来返回每个项目.如果一个项目有2个以上类别不同的​​条目，那么我只需要选择一次该项目(为该项目选择哪个条目都没关系).

So each project is returned based on whether its project_num and title are unique. If a project has 2+ entries where its category is different, I need to only select that project once (it doesn't matter which entry I select for that project).

有人可以帮我吗?

推荐答案

SELECT Project_Num, Title, MIN(Category) AS Category
FROM MyTable
GROUP BY Project_Num, Title;

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