需要不同的逗号分隔的产品值按日期排序

Question

我有下面的表结构

create TABLE PRODUCTDeatils 
(
    Product varchar(50),
    Date Datetime
)

我想要一个输出，其中我得到具有不同值但按日期排序的逗号分隔列表。

我首先通过以下查询拆分值

SELECT DISTINCT
    LTRIM(RTRIM(value)) AS Product, date
INTO #tmp3
FROM PRODUCTDeatils
CROSS APPLY STRING_SPLIT(LTRIM(RTRIM(Product)), ',')    

SELECT * 
FROM #tmp3 
ORDER BY date

然后我使用以下两个查询来实现它但没有成功。

查询 #1：

DECLARE @cols AS NVARCHAR(MAX);

SELECT @COLS =  substring(list, 1, LEN(list) - 1)
FROM   
    (SELECT 
         list = (SELECT DISTINCT Product + ';'
                 FROM #tmp3
                 ORDER BY Product + ';'
                 FOR XML PATH(''), TYPE).value('.', 'nvarchar(MAX)')) AS T

SELECT @COLS

查询 #2：

 SELECT  
     STUFF((SELECT '; ' + Product
            FROM 
                (SELECT DISTINCT TOP 100
                     Product,date
                 FROM #tmp3) x  
            ORDER BY date
            FOR XML PATH('')), 1, 2, '') Text

我想要上面的输出，但 bat 应该只出现一次。

Answer 1

在较新版本的 SQL Server 中，您应该只使用string_agg()：

SELECT STRING_AGG(Product, ',') WITHIN GROUP (ORDER BY date)
FROM (SELECT LTRIM(RTRIM(s.value)) AS Product, MIN(date) as date
      FROM ProductDetails pd CROSS APPLY
           STRING_SPLIT(LTRIM(RTRIM(pd.Product)), ',') s 
      GROUP BY LTRIM(RTRIM(s.value))
     ) p

Here 是一个 dbfiddle。

Answer 2

您可以添加row_number 并为每个产品选择一个值。

SELECT DISTINCT
    LTRIM(RTRIM(value)) AS Product, date, ROW_NUMBER() over (partition by trim(Value) order by date) rn
INTO #tmp3
FROM PRODUCTDeatils
CROSS APPLY STRING_SPLIT(LTRIM(RTRIM(Product)), ',')    

SELECT  
     STUFF((SELECT '; ' + Product
            FROM 
                (SELECT DISTINCT TOP 100
                     Product,date
                 FROM #tmp3 where rn = 1) x  
            ORDER BY date
            FOR XML PATH('')), 1, 2, '') Text

请找到 dbfiddle here。