查询将一列中的 2 行合并为 1 行和 2 列

Question

我需要处理查询字符串并从中创建记录。

最初格式是转义字符串，格式如下：

relativeFilePath1^relativeFilePath2^relativeFilePath3^relativeFilePath4

其中 ^ 字符使用 %5E 转义。用于在此位置拆分字符串，创建临时 table，将所有内容插入其中并从那里触发插入。

DECLARE @SplittetList TABLE(ID int Identity(1,1), fPath nvarchar(max));
INSERT INTO @SplittetList SELECT * FROM Schema.fnSplit('relativeFilePath1%5ErelativeFilePath2%5ErelativeFilePath3%5ErelativeFilePath4', '%5E')
--additional processing

现在格式即将更改，以便在每个文件路径之后，还有此文件的附加元数据字段，也用 ^ 字符分隔。如果我现在拆分它，我会得到这样的结果：

ID |  fPath
---------------------
1  |  relativeFilePath1
2  |  metadata1
3  |  relativeFilePath2
4  |  metadata2
5  |  relativeFilePath3
6  |  metadata3
n  |  ...

我怎样才能转换这个列表，以便结果是一组这种格式的数据：

filepath           |     metadata
----------------------------------
relativeFilePath1  |     metadata1
relativeFilePath2  |     metadata2
relativeFilePath3  |     metadata3
...

Answer 1

DECLARE @Data table
(
    ID int identity(1,1),
    fPath nvarchar(max)
)

insert @Data values
('relativeFilePath1'),('metadata1'),('relativeFilePath2'),('metadata2'),('relativeFilePath3'),('metadata3')

-- ROW_NUMBER to ensure the ID is continuous
;with data as 
(
    select *, 
        (ROW_NUMBER() OVER (ORDER BY Id)+1)/2 as grp, 
        (ROW_NUMBER() OVER (ORDER BY Id)+1)%2 as columnno 
    from @Data
)
-- Subquery verison
select 
    (select fPath from data where grp = d.grp and columnno = 0) as filepath, 
    (select fPath from data where grp = d.grp and columnno = 1) as metadata
from data d group by grp

-- Inner join version
--select a.fPath, b.fPath from data a inner join data b on a.grp = b.grp
--where a.columnno = 0 and b.columnno = 1

查询将一列中的 2 行合并为 1 行和 2 列

Query to merge 2 rows from one column into 1 row with 2 columns

sql

tsql

sql-server-2008-r2