在 SQL 服务器中将行转置为列，我尝试使用数据透视表，但未达到预期结果

Question

在 SQL 服务器中将行转换为列，我尝试使用 pivot 但是没有达到预期结果，使用 pivot 仅获取最大值

CREATE TABLE [dbo].[test]
(
    [patientid] [int] NULL,
    [sourcename] [varchar](200) NULL,
    [identifier] [varchar](100) NULL
) ON [PRIMARY]
GO

INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'SIN', N'2663563')
INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'SIN', N'2453433')
INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'MED', N'534545')
INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'MED', N'212334')
INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'NXG', N'8678')
INSERT [dbo].[test] ([patientid], [sourcename], [identifier]) 
VALUES (100, N'NXG', N'2131232334')

预期输出：

Answer 1

使用row_number()和条件聚合：

select patientid,
    max(case when sourcename = 'SIN' then identifier end) as sin,
    max(case when sourcename = 'MED' then identifier end) as med,
    max(case when sourcename = 'NXG' then identifier end) as nxg
from (
    select t.*, row_number() over(partition by sourcename, sourcename order by identifier) rn
    from test t
) t
group by patientid, rn

Answer 2

您可以将条件聚合与 row_number() 一起使用：

select partitionid,
       max(case when sourcename = 'SIN' then identifier end) as sin,
       max(case when sourcename = 'MED' then identifier end) as med,
       max(case when sourcename = 'NXG' then identifier end) as nxg
from (select t.*,
             row_number() over (partition by partitionid, sourcename order by identifier) as seqnum
      from t
     ) t
group by partitionid, seqnum

在 SQL 服务器中将行转置为列，我尝试使用数据透视表，但未达到预期结果

Transpose rows into columns in SQL Server, I try it using pivot but, expected result is not reached

sql

sql-server

pivot

aggregate-functions