如何在SQL Server中透视未知的列数且没有聚合？

小编典典

如何在SQL Server中透视未知的列数且没有聚合？

sql

我有一个查询，该查询返回具有相关抵押名称的客户贷款，如以下（1）所示，但我想连续仅拥有一个不同的贷款编号，并且像其他示例（2）那样保留抵押名称。一直在进行透视，但由于我没有汇总列，也不知道要解决的原因，我也不知道每笔贷款可能没有多少抵押品。怎么做？？？在SQL Server 2012中可能吗？

谢谢

（1）

loanid|name  |Address |
1     |John  |New York|
1     |Carl  |New York|
1     |Henry |Boston  |
2     |Robert|Chicago |
3     |Joanne|LA      |
3     |Chris |LA      |

（2）我需要这样的东西

loanid|name  |address  |name |address |name|address|
1     |Jonh  |New York |Carl |New York|Henry|Boston|
2     |Robert|Chicago  |
3     |Joanne|LA       |Chris|LA|

阅读 279

2021-04-24

共1个答案

小编典典

测试数据

DECLARE @TABLE TABLE (loanid INT,name VARCHAR(20),[Address] VARCHAR(20))
INSERT INTO @TABLE VALUES
(1,'John','New York'),(1,'Carl','New York'),(1,'Henry','Boston'),
(2,'Robert','Chicago'),(3,'Joanne','LA'),(3,'Chris','LA')

询问

SELECT  loanid
       ,ISNULL(name1, '')    AS name1
       ,ISNULL(Address1, '') AS Address1
       ,ISNULL(name2, '')    AS name2
       ,ISNULL(Address2, '') AS Address2
       ,ISNULL(name3, '')    AS name3
       ,ISNULL(Address3, '') AS Address3
FROM (
SELECT loanid
      ,'name' + CAST(ROW_NUMBER() OVER (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) AS Cols
      , name AS Vals
FROM @TABLE
UNION ALL
SELECT loanid
      ,'Address' + CAST(ROW_NUMBER() OVER (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) 
      , [Address] 
FROM @TABLE ) t
 PIVOT (MAX(Vals)
        FOR Cols 
        IN (name1, Address1,name2,Address2,name3,Address3)
        )P

结果集

╔════════╦════════╦══════════╦═══════╦══════════╦═══════╦══════════╗
║ loanid ║ name1  ║ Address1 ║ name2 ║ Address2 ║ name3 ║ Address3 ║
╠════════╬════════╬══════════╬═══════╬══════════╬═══════╬══════════╣
║      1 ║ John   ║ New York ║ Carl  ║ New York ║ Henry ║ Boston   ║
║      2 ║ Robert ║ Chicago  ║       ║          ║       ║          ║
║      3 ║ Joanne ║ LA       ║ Chris ║ LA       ║       ║          ║
╚════════╩════════╩══════════╩═══════╩══════════╩═══════╩══════════╝

动态列更新

DECLARE @Cols NVARCHAR(MAX);

SELECT @Cols =  STUFF((
                    SELECT DISTINCT ', ' +  QUOTENAME(Cols)
                    FROM (
                    SELECT loanid
                          ,'name' + CAST(ROW_NUMBER() OVER (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) AS Cols
                          , name AS Vals
                    FROM @TABLE
                    UNION ALL
                    SELECT loanid
                          ,'Address' + CAST(ROW_NUMBER() OVER (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) 
                          , [Address] 
                    FROM @TABLE ) t
                    GROUP BY QUOTENAME(Cols)
                    FOR XML PATH(''), TYPE).value('.','NVARCHAR(MAX)'),1,2,'')


DECLARE @Sql NVARCHAR(MAX);

SET @Sql  = 'SELECT ' + @Cols +   '
            FROM (
            SELECT loanid
                  ,''name'' + CAST(ROW_NUMBER() OVER 
                            (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) AS Cols
                  , name AS Vals
            FROM @TABLE
            UNION ALL
            SELECT loanid
                  ,''Address'' + CAST(ROW_NUMBER() OVER 
                                (PARTITION BY loanid ORDER BY loanid)  AS NVARCHAR(10)) 
                  , [Address] 
            FROM @TABLE ) t
             PIVOT (MAX(Vals)
                    FOR Cols 
                    IN (' + @Cols + ')
                    )P'

EXECUTE sp_executesql @Sql

笔记

这将无法与我的答案中给定的示例数据一起使用，因为它使用表变量，并且由于它具有自己的作用域，因此对于动态sql不可见。但是此解决方案可以在普通的sql server表上使用。

同样，选择列的顺序也会略有不同。

2021-04-24