Sql server 2008 如何将值拆分为多行?
我有一张这样的桌子Sql server 2008 如何将值拆分为多行?,sql-server-2008,Sql Server 2008,我有一张这样的桌子 keytype keyvalue ---------------------------- type1 st1,st2,st3 -------------------------------- type2 ts1,ts2,ts3 type1 type2 ------------------------ st1 ts1 ----------------- st2 ts2 ------
keytype keyvalue
----------------------------
type1 st1,st2,st3
--------------------------------
type2 ts1,ts2,ts3
type1 type2
------------------------
st1 ts1
-----------------
st2 ts2
--------------------
st3 ts3
我想像这样将数据插入一个临时表中
keytype keyvalue
----------------------------
type1 st1,st2,st3
--------------------------------
type2 ts1,ts2,ts3
type1 type2
------------------------
st1 ts1
-----------------
st2 ts2
--------------------
st3 ts3
我该怎么做。请告诉我。谢谢。您应该以关系方式存储此数据,而不是以CSV字符串形式存储多条数据。如果您无法修复设计,那么这里有一种方法可以修复,但它会做出一些假设:(a)您只需要两种类型(b)这些类型具有相同数量的逗号分隔值。如果有两行以上的数据,则扩展并不十分麻烦,但除非您想恢复到非常单调的动态SQL,否则您需要提前知道有多少行 首先,创建一个有序拆分函数:
CREATE FUNCTION [dbo].[SplitStrings_Ordered]
(
@List NVARCHAR(MAX),
@Delimiter NVARCHAR(255)
)
RETURNS TABLE
AS
RETURN (SELECT [Index] = ROW_NUMBER() OVER (ORDER BY Number), Item
FROM (SELECT Number, Item = SUBSTRING(@List, Number,
CHARINDEX(@Delimiter, @List + @Delimiter, Number) - Number)
FROM (SELECT ROW_NUMBER() OVER (ORDER BY s1.[object_id])
FROM sys.all_objects AS s1 CROSS JOIN sys.all_objects AS s2) AS n(Number)
WHERE Number <= CONVERT(INT, LEN(@List))
AND SUBSTRING(@Delimiter + @List, Number, LEN(@Delimiter)) = @Delimiter
) AS y);
GO
您可以对源表连接两个使用交叉应用的CTE:
;WITH t1 AS
(
SELECT s.[Index], s.Item FROM @x AS x
CROSS APPLY dbo.SplitStrings_Ordered(x.keyvalue, ',') AS s
WHERE x.keytype = 'type1'
), t2 AS
(
SELECT s.[Index], s.Item FROM @x AS x
CROSS APPLY dbo.SplitStrings_Ordered(x.keyvalue, ',') AS s
WHERE x.keytype = 'type2'
)
-- INSERT #some_temp_table(columns)
SELECT type1 = t1.Item, type2 = t2.Item
FROM t1 INNER JOIN t2 ON t1.[Index] = t2.[Index]
ORDER BY t1.[Index];
为什么要将JSON塞进一列?您是否只有2个键类型,或者这需要容纳任意数量的源行?当一个JSON字符串有3个项目,另一个有4个项目时,您希望发生什么?