在逗号分隔值的Sql查询连接
问题描述：
我有一个具有复合键和逗号分隔值的表。我需要为每个逗号分隔的元素将单行分割成一行。我看到过类似的问题和类似的答案，但一直未能将它们转化为我自己的解决方案。在逗号分隔值的Sql查询连接
我正在运行SQL Server 2008 R2。
| Key Part 1 | Key Part 2 | Key Part 3 | Values |
|------------------------------------------------------|
| A | A | A | PDE,PPP,POR |
| A | A | B | PDE,XYZ |
| A | B | A | PDE,RRR |
|------------------------------------------------------|
，我需要这个作为输出
| Key Part 1 | Key Part 2 | Key Part 3 | Values | Sequence |
|-------------------------------------------------------------------|
| A | A | A | PDE | 0 |
| A | A | A | PPP | 1 |
| A | A | A | POR | 2 |
| A | A | B | PDE | 0 |
| A | A | B | XYZ | 1 |
| A | B | A | PDE | 0 |
| A | B | A | RRR | 1 |
|-------------------------------------------------------------------|
感谢
杰夫
答
下面是一个简单的内联的方式，如果你没有或者不想拆分/解析UDF
示例
Select A.[Key Part 1]
,A.[Key Part 2]
,A.[Key Part 3]
,B.*
From YourTable A
Cross Apply (
Select [Values] = LTrim(RTrim(X2.i.value('(./text())[1]', 'varchar(max)')))
,[Sequence] = Row_Number() over (Order By (Select null))-1
From (Select x = Cast('<x>' + replace(A.[Values],',','</x><x>')+'</x>' as xml)) X1
Cross Apply x.nodes('x') X2(i)
) B
返回
编辑 - 如果打开的表值函数
查询应该是这样的
Select A.[Key Part 1]
,A.[Key Part 2]
,A.[Key Part 3]
,[Values] = B.RetVal
,[Sequence] = B.RetSeq-1
From @YourTable A
Cross Apply [dbo].[udf-Str-Parse-8K](A.[Values],',') B
的UDF如果有兴趣
CREATE FUNCTION [dbo].[udf-Str-Parse-8K] (@String varchar(max),@Delimiter varchar(25))
Returns Table
As
Return (
with cte1(N) As (Select 1 From (Values(1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) N(N)),
cte2(N) As (Select Top (IsNull(DataLength(@String),0)) Row_Number() over (Order By (Select NULL)) From (Select N=1 From cte1 a,cte1 b,cte1 c,cte1 d) A),
cte3(N) As (Select 1 Union All Select t.N+DataLength(@Delimiter) From cte2 t Where Substring(@String,t.N,DataLength(@Delimiter)) = @Delimiter),
cte4(N,L) As (Select S.N,IsNull(NullIf(CharIndex(@Delimiter,@String,s.N),0)-S.N,8000) From cte3 S)
Select RetSeq = Row_Number() over (Order By A.N)
,RetVal = LTrim(RTrim(Substring(@String, A.N, A.L)))
From cte4 A
);
--Orginal Source http://www.sqlservercentral.com/articles/Tally+Table/72993/
--Select * from [dbo].[udf-Str-Parse-8K]('Dog,Cat,House,Car',',')
--Select * from [dbo].[udf-Str-Parse-8K]('John||Cappelletti||was||here','||')
答
如果所有CSV值恰好3个字符（如你在测试数据有），你可以通过创建使用一款符合表中一个非常有效的方式需要预先确定的行数（与为每个字符创建一行以查找分隔符字符相反）...因为您已经知道分隔符位置。
在这种情况下，我将使用一个理货函数，但您也可以使用一个固定理货表。
代码为tfn_Tally功能...
SET QUOTED_IDENTIFIER ON
SET ANSI_NULLS ON
GO
CREATE FUNCTION dbo.tfn_Tally
/* ============================================================================
07/20/2017 JL, Created. Capable of creating a sequense of rows
ranging from -10,000,000,000,000,000 to 10,000,000,000,000,000
============================================================================ */
(
@NumOfRows BIGINT,
@StartWith BIGINT
)
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
WITH
cte_n1 (n) AS (SELECT 1 FROM (VALUES (1),(1),(1),(1),(1),(1),(1),(1),(1),(1)) n (n)), -- 10 rows
cte_n2 (n) AS (SELECT 1 FROM cte_n1 a CROSS JOIN cte_n1 b), -- 100 rows
cte_n3 (n) AS (SELECT 1 FROM cte_n2 a CROSS JOIN cte_n2 b), -- 10,000 rows
cte_n4 (n) AS (SELECT 1 FROM cte_n3 a CROSS JOIN cte_n3 b), -- 100,000,000 rows
cte_Tally (n) AS (
SELECT TOP (@NumOfRows)
(ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) - 1) + @StartWith
FROM
cte_n4 a CROSS JOIN cte_n4 b -- 10,000,000,000,000,000 rows
)
SELECT
t.n
FROM
cte_Tally t;
GO
如何解决使用它...
-- create some test data...
IF OBJECT_ID('tempdb..#TestData', 'U') IS NOT NULL
DROP TABLE #TestData;
CREATE TABLE #TestData (
KeyPart1 CHAR(1),
KeyPart2 CHAR(1),
KeyPart3 CHAR(1),
[Values] varchar(50)
);
INSERT #TestData (KeyPart1, KeyPart2, KeyPart3, [Values]) VALUES
('A', 'A', 'A', 'PDE,PPP,POR'),
('A', 'A', 'B', 'PDE,XYZ'),
('A', 'B', 'A', 'PDE,RRR,XXX,YYY,ZZZ,AAA,BBB,CCC');
--==========================================================
-- solution query...
SELECT
td.KeyPart1,
td.KeyPart2,
td.KeyPart3,
x.SplitValue,
[Sequence] = t.n
FROM
#TestData td
CROSS APPLY dbo.tfn_Tally(LEN(td.[Values]) - LEN(REPLACE(td.[Values], ',', '')) + 1, 0) t
CROSS APPLY (VALUES (SUBSTRING(td.[Values], t.n * 4 + 1, 3))) x (SplitValue);
而且结果...
KeyPart1 KeyPart2 KeyPart3 SplitValue Sequence
-------- -------- -------- ---------- --------------------
A A A PDE 0
A A A PPP 1
A A A POR 2
A A B PDE 0
A A B XYZ 1
A B A PDE 0
A B A RRR 1
A B A XXX 2
A B A YYY 3
A B A ZZZ 4
A B A AAA 5
A B A BBB 6
A B A CCC 7
如果假设所有csv元素都是字符数是不正确的，你最好使用传统的基于tally的分离器。在这种情况下，我的建议是DelimitedSplit8K written by Jeff Moden。
在这种情况下，解决方案查询将如下所示...
SELECT
td.KeyPart1,
td.KeyPart2,
td.KeyPart3,
SplitValue = dsk.Item,
[Sequence] = dsk.ItemNumber - 1
FROM
#TestData td
CROSS APPLY dbo.DelimitedSplit8K(td.[Values], ',') dsk;
安结果...
KeyPart1 KeyPart2 KeyPart3 SplitValue Sequence
-------- -------- -------- ---------- --------------------
A A A PDE 0
A A A PPP 1
A A A POR 2
A A B PDE 0
A A B XYZ 1
A B A PDE 0
A B A RRR 1
A B A XXX 2
A B A YYY 3
A B A ZZZ 4
A B A AAA 5
A B A BBB 6
A B A CCC 7
HTH，杰森
答
- 创建表
Create table YourTable
(
p1 varchar(50),
p2 varchar(50),
p3 varchar(50),
pval varchar(50)
)
go
- 插入数据
insert into YourTable values ('A','A','A','PDE,PPP,POR'),
('A','A','B','PDE,XYZ'),('A','B','A','PDE,RRR')
go
- 查看样本数据
SELECT p1, p2, p3 , pval FROM YourTable
go
- 所需的结果
SELECT p1,p2,p3, LTRIM(RTRIM(Split.a.value('.', 'VARCHAR(100)'))) as Value1 , ROW_NUMBER() OVER(PARTITION BY id ORDER BY id ASC)-1 AS SequenceNo
FROM
(SELECT ROW_NUMBER() over (order by (SELECT NULL)) AS ID, p1,p2,p3, pval, CAST ('<M>' + REPLACE(pval, ',', '</M><M>') + '</M>' AS XML) AS Data from YourTable
) AS A
CROSS APPLY Data.nodes ('/M') AS Split(a)
go
- 删除临时创建的表
drop table YourTable
go
是否所有的元素恰好3个字符每个，因为它们在你例子？ –
您应该**不**在单个单元格中以逗号分隔形式存储多个值。首先，正如你所看到的，后来使用这些数据是一团糟和艰苦的工作，而且它也违反了**关系数据库设计的第一种常规形式。 –