Question

在SQL Server 2012表中，我想从两列中获取所有行，并将它们转换为一行，仍然是两列，但每列都以逗号分隔。

例如

Customerid    |    FacilityId
-----------------------------
1                    5678
2                    9101
5                    6543

之后我觉得结果就像这样

Customerid    |    FacilityId
-----------------------------
1,2,5            5678,9101,6543

Answer 1

您可以像SQL Fiddle

一样使用FOR XML

<强>查询

SELECT STUFF((
SELECT ',' + CONVERT(VARCHAR(10),Customerid)
FROM Customer
FOR XML PATH('')),1,1,'') as Customerid,
STUFF((
SELECT ',' + CONVERT(VARCHAR(10),FacilityId)
FROM Customer
FOR XML PATH('')),1,1,'') as FacilityId

<强>输出

Customerid  FacilityId
1,2,5   5678,9101,6543

修改

您甚至可以使用变量将csv连接在一起，这不需要像FOR XML这样的2个表扫描，但是当您在同一查询中使用ORDER BY或其他函数时可能会遇到问题。

由于您只有3-4行，我建议使用FOR XML方法

DECLARE @Customerid VARCHAR(MAX) = '',@FacilityId VARCHAR(MAX) = '' SELECT @Customerid += ',' + CONVERT(VARCHAR(10),Customerid), @FacilityId += ',' + CONVERT(VARCHAR(10),FacilityId) FROM Customer SELECT STUFF(@Customerid,1,1,'') as Customerid, STUFF(@FacilityId,1,1,'') as FacilityId

Answer 2

使用CONCAT这是一种简单快捷的方法，它可以在sqlserver 2012中使用：

DECLARE @t table(Customerid int, FacilityId int)
INSERT @t values(1,5678),(2,9101),(5,6543)

DECLARE @x1 varchar(max), @x2 varchar(max)

SELECT 
  @x1 = concat(@x1 + ',', Customerid), 
  @x2 = concat(@x2 + ',', FacilityId)
FROM @t

SELECT @x1, @x2

Answer 3

你可以这样做：

SELECT * FROM
(SELECT Customerid = STUFF((
          SELECT ',' + CAST(md.Customerid as varchar(max))
          FROM dbo.TableName md
          FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, ''),
        Facilityid=STUFF((
          SELECT ',' + CAST(md.Facilityid as varchar(max))
          FROM dbo.TableName md
          FOR XML PATH(''), TYPE).value('.', 'NVARCHAR(MAX)'), 1, 1, '')
FROM dbo.TableName m
JOIN dbo.TableName s ON s.customerid = m.customerid AND s.facilityid=m.facilityid) as Tbl
GROUP BY customerid,facilityid

结果：

Customerid  Facilityid
--------------------------
1,2,5       5678,9101,6543

SQL Fiddle

中的示例结果

Answer 4

在SQL SERVER中使用FOR XML PATH

SELECT (SELECT CAST(Customerid AS VARCHAR) + ',' from 
                   Table for XML PATH(''), type).value('.', 'varchar(max)') AS Customerid, 
    (SELECT CAST(FacilityId AS VARCHAR) + ',' from 
                   Table for XML PATH(''), type).value('.', 'varchar(max)') AS FacilityId

Answer 5

您可以STUFF使用FOR XML来实现此目的：

CREATE TABLE #tmpDemo (CustomerId INT, FacilityId INT)
INSERT INTO #tmpDemo VALUES (1, 5678), (2, 9101), (5, 6543)

SELECT  DISTINCT
        STUFF((
          SELECT ',' + CAST(T.CustomerId AS VARCHAR)
          FROM #tmpDemo T
          FOR XML PATH('')), 1, 1, '') as CustomerId,
        STUFF((
          SELECT ',' + CAST(T.FacilityId AS VARCHAR)
          FROM #tmpDemo T
          FOR XML PATH('')), 1, 1, '') as FacilityId
FROM #tmpDemo m

DROP TABLE #tmpDemo

这可能会导致大型数据集出现严重的性能问题，但我从上面的评论中注意到，您只会拥有少量行。

Answer 6

使用COALESCE

DECLARE @Names VARCHAR(8000) 
DECLARE @id VARCHAR(8000) 

SELECT @id = COALESCE(@id + ', ', '') + CAST(col1 AS VARCHAR),@Names = COALESCE(@Names + ', ', '') + col2
FROM tab1

select @id,@Names

<强> SQLFiddle Demo

逗号分开两个单独的列

6 个答案: