SQL数据库查询为一个值选择不同的对应值

Question

如何从表中得到这样的输出？如果我有一个如下所示的表格

First Name         Last Name
----------    

 1. John            Doe
 2. John           Ruggles
 3. Ricky          Rog
 4. kelly          Ali
 5. Ricky           Gyri

我想显示如下

First Name       Last Name

 1.John           Doe
                  Ruggles

 2. Kelly         Ali

 3. Ricky         Rog
                  Gyri

就像我想显示姓氏的每个名字一样。我希望名字只出现一次。请帮我。它是一个表格数据，名字和姓氏是不同的列

Answer 1

您可以使用 row_number() analytic function确定姓氏是否已更改:

select  case
        when row_number() over (partition by FirstName 
                                order by FirstName, LastName) = 1 
            then FirstName
        else ''
        end as FirstName
,       LastName
from    YourTable
order by
        YourTable.FirstName
,       LastName

Example at SQL Fiddle.