如何在SQL Server中对类似数据进行分组

Question

我有这样的输出：

foldername    setname           testname           step     stepdescription    
------------------------------------------------------------------------------
name1.0       setname 1.1.1     testname1          step1       stpdes5         
name2.1       setname 1.0.0     testname2          step1       asdf5           
name2.1       setname 1.0.0     testname2          step2       ;lkj10          
name2.1       setname 1.0.0     testname2          step3       aaaaaa10        
name3         setname 1.2.1     testname3          step1       nnnn10  

我想以下面的方式输出：

foldername    setname           testname           step     stepdescription    
----------------------------------------------------------------------------
name1.0       setname 1.1.1     testname1          step1       stpdes5         
name2.1       setname 1.0.0     testname2          step1       asdf5           
                                                   step2       lkj10          
                                                   step3       aaaaaa10        
name3         setname 1.2.1     testname3          step1       nnnn10           

Answer 1

您可以使用ROW_NUMBER

执行此操作

SELECT case when seq >1 THEN '' ELSE foldername END as foldername,
       case when seq >1 THEN '' ELSE setname END as setname,
       case when seq >1 THEN '' ELSE testname END as testname,
       step,
       stepdescription
FROM
(
SELECT *,
     ROW_NUMBER() OVER ( PARTITION BY foldername, setname, testname order by (select NULL) ) as seq
FROM Table1
) T