选择“唯一字段"和“行号"只是为了显示一个ID号，将得到重复的数据 [英] Selecting Distinct field and row num just to display an id number gives duplicated data

问题描述

我有一个表应用程序，它有10列.类别是一列，​​并且此列具有重复的值.为了获得不同的值，我有一个查询

I have a table application and it has 10 columns. category is one column and this column has duplicated values. To get distinct values I have a query

从"APPLICATION"中选择"Category"作为CategoryName，其中applicationId =?.

我得到的结果没有任何问题.现在，我想在此处添加另一列作为categoryId.没有这样的字段，我必须生成一个.我尝试了以下查询.

I am getting result without any issue. Here now I wanted to add a another column as categoryId. There is no such field, I have to generate one. I tried with below query.

SELECT distinct(CATEGORY) as CategoryName , rownum as categoryId FROM APPLICATION where applicationId=?

然后显示重复的类别，其中rownum为id.我可以使用任何数字作为ID，但类别名称不应重复.谁能在一个查询中建议如何做到这一点.

Then it shows duplicate category with the rownum as id. I am ok with any number as id but category name should not duplicated. Can any one suggests how to do it in a single query.

推荐答案

请使用

SELECT CATEGORY as CategoryName, sum(rownum) FROM APPLICATION WHERE applicationId=? GROUP BY CATEGORY

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