我有一个像这样的SQL表：
| SomeID | OtherID | Data
+----------------+-------------+-------------------
| abcdef-..... | cdef123-... | 18,20,22
| abcdef-..... | 4554a24-... | 17,19
| 987654-..... | 12324a2-... | 13,19,20
是否有查询，我可以执行像SELECT OtherID, SplitData WHERE SomeID = 'abcdef-.......'这样的查询，返回单个行，如下所示：
| OtherID | SplitData
+-------------+-------------------
| cdef123-... | 18
| cdef123-... | 20
| cdef123-... | 22
| 4554a24-... | 17
| 4554a24-... | 19
基本上将逗号中的数据拆分为单独的行？
我知道将comma-separated字符串存储到关系数据库中听起来很愚蠢，但消费者应用程序中的正常用例使得这非常有用。
我不想在应用程序中进行拆分，因为我需要分页，因此我想在重构整个应用程序之前探索选项。
它是SQL Server 2008（非R2）。
答案 0 :(得分：231)
您可以使用SQL Server中精彩的递归函数：
样本表：
CREATE TABLE Testdata
(
SomeID INT,
OtherID INT,
String VARCHAR(MAX)
)
INSERT Testdata SELECT 1, 9, '18,20,22'
INSERT Testdata SELECT 2, 8, '17,19'
INSERT Testdata SELECT 3, 7, '13,19,20'
INSERT Testdata SELECT 4, 6, ''
INSERT Testdata SELECT 9, 11, '1,2,3,4'
查询
;WITH tmp(SomeID, OtherID, DataItem, String) AS
(
SELECT
SomeID,
OtherID,
LEFT(String, CHARINDEX(',', String + ',') - 1),
STUFF(String, 1, CHARINDEX(',', String + ','), '')
FROM Testdata
UNION all
SELECT
SomeID,
OtherID,
LEFT(String, CHARINDEX(',', String + ',') - 1),
STUFF(String, 1, CHARINDEX(',', String + ','), '')
FROM tmp
WHERE
String > ''
)
SELECT
SomeID,
OtherID,
DataItem
FROM tmp
ORDER BY SomeID
-- OPTION (maxrecursion 0)
-- normally recursion is limited to 100. If you know you have very long
-- strings, uncomment the option
<强>输出
SomeID | OtherID | DataItem
--------+---------+----------
1 | 9 | 18
1 | 9 | 20
1 | 9 | 22
2 | 8 | 17
2 | 8 | 19
3 | 7 | 13
3 | 7 | 19
3 | 7 | 20
4 | 6 |
9 | 11 | 1
9 | 11 | 2
9 | 11 | 3
9 | 11 | 4
答案 1 :(得分：108)
最后， SQL Server 2016 等待已经结束。他们引入了Split字符串函数STRING_SPLIT：
select OtherID, cs.Value --SplitData
from yourtable
cross apply STRING_SPLIT (Data, ',') cs
所有其他分割字符串的方法，如XML，Tally表，while循环等等，都被这个STRING_SPLIT函数所震撼。
以下是一篇包含性能比较的优秀文章： Performance Surprises and Assumptions: STRING_SPLIT 。
对于旧版本，使用计数表这里是一个拆分字符串函数（最好的方法）
CREATE FUNCTION [dbo].[DelimitedSplit8K]
(@pString VARCHAR(8000), @pDelimiter CHAR(1))
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 0 up to 10,000...
-- enough to cover NVARCHAR(4000)
WITH E1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
), --10E+1 or 10 rows
E2(N) AS (SELECT 1 FROM E1 a, E1 b), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a, E2 b), --10E+4 or 10,000 rows max
cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
-- for both a performance gain and prevention of accidental "overruns"
SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
SELECT 1 UNION ALL
SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
SELECT s.N1,
ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1,8000)
FROM cteStart s
)
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
Item = SUBSTRING(@pString, l.N1, l.L1)
FROM cteLen l
;
答案 2 :(得分：80)
检查
SELECT A.OtherID,
Split.a.value('.', 'VARCHAR(100)') AS Data
FROM
(
SELECT OtherID,
CAST ('<M>' + REPLACE(Data, ',', '</M><M>') + '</M>' AS XML) AS Data
FROM Table1
) AS A CROSS APPLY Data.nodes ('/M') AS Split(a);
答案 3 :(得分：17)
select t.OtherID,x.Kod
from testData t
cross apply (select Code from dbo.Split(t.Data,',') ) x
答案 4 :(得分：12)
截至2016年2月 - 参见TALLY表示例 - 从2014年2月起，很可能在下面的TVF中表现优异。保留以下原始帖子给后人：
在上面的示例中，我喜欢重复的代码太多了。我不喜欢CTE和XML的性能。此外，显式Id以便特定订单的消费者可以指定ORDER BY子句。
CREATE FUNCTION dbo.Split
(
@Line nvarchar(MAX),
@SplitOn nvarchar(5) = ','
)
RETURNS @RtnValue table
(
Id INT NOT NULL IDENTITY(1,1) PRIMARY KEY CLUSTERED,
Data nvarchar(100) NOT NULL
)
AS
BEGIN
IF @Line IS NULL RETURN
DECLARE @split_on_len INT = LEN(@SplitOn)
DECLARE @start_at INT = 1
DECLARE @end_at INT
DECLARE @data_len INT
WHILE 1=1
BEGIN
SET @end_at = CHARINDEX(@SplitOn,@Line,@start_at)
SET @data_len = CASE @end_at WHEN 0 THEN LEN(@Line) ELSE @end_at-@start_at END
INSERT INTO @RtnValue (data) VALUES( SUBSTRING(@Line,@start_at,@data_len) );
IF @end_at = 0 BREAK;
SET @start_at = @end_at + @split_on_len
END
RETURN
END
答案 5 :(得分：6)
很高兴看到它已经在2016版本中得到了解决，但是对于所有那些没有解决的问题，这里是上述方法的两个通用和简化版本。
XML方法更短，但当然要求字符串允许xml-trick（没有'坏'字符。）
<强> XML-方法：
create function dbo.splitString(@input Varchar(max), @Splitter VarChar(99)) returns table as
Return
SELECT Split.a.value('.', 'VARCHAR(max)') AS Data FROM
( SELECT CAST ('<M>' + REPLACE(@input, @Splitter, '</M><M>') + '</M>' AS XML) AS Data
) AS A CROSS APPLY Data.nodes ('/M') AS Split(a);
递归方法：
create function dbo.splitString(@input Varchar(max), @Splitter Varchar(99)) returns table as
Return
with tmp (DataItem, ix) as
( select @input , CHARINDEX('',@Input) --Recu. start, ignored val to get the types right
union all
select Substring(@input, ix+1,ix2-ix-1), ix2
from (Select *, CHARINDEX(@Splitter,@Input+@Splitter,ix+1) ix2 from tmp) x where ix2<>0
) select DataItem from tmp where ix<>0
行动中的功能
Create table TEST_X (A int, CSV Varchar(100));
Insert into test_x select 1, 'A,B';
Insert into test_x select 2, 'C,D';
Select A,data from TEST_X x cross apply dbo.splitString(x.CSV,',') Y;
Drop table TEST_X
XML-METHOD 2：Unicode Friendly （Max Hodges提供）
create function dbo.splitString(@input nVarchar(max), @Splitter nVarchar(99)) returns table as
Return
SELECT Split.a.value('.', 'NVARCHAR(max)') AS Data FROM
( SELECT CAST ('<M>' + REPLACE(@input, @Splitter, '</M><M>') + '</M>' AS XML) AS Data
) AS A CROSS APPLY Data.nodes ('/M') AS Split(a);
答案 6 :(得分：3)
DECLARE @id_list VARCHAR(MAX) = '1234,23,56,576,1231,567,122,87876,57553,1216'
DECLARE @table TABLE ( id VARCHAR(50) )
DECLARE @x INT = 0
DECLARE @firstcomma INT = 0
DECLARE @nextcomma INT = 0
SET @x = LEN(@id_list) - LEN(REPLACE(@id_list, ',', '')) + 1 -- number of ids in id_list
WHILE @x > 0
BEGIN
SET @nextcomma = CASE WHEN CHARINDEX(',', @id_list, @firstcomma + 1) = 0
THEN LEN(@id_list) + 1
ELSE CHARINDEX(',', @id_list, @firstcomma + 1)
END
INSERT INTO @table
VALUES ( SUBSTRING(@id_list, @firstcomma + 1, (@nextcomma - @firstcomma) - 1) )
SET @firstcomma = CHARINDEX(',', @id_list, @firstcomma + 1)
SET @x = @x - 1
END
SELECT *
FROM @table
答案 7 :(得分：2)
请参考下面的TSQL。 STRING_SPLIT函数仅在兼容级别130及更高版本下可用。
TSQL：
DECLARE @stringValue NVARCHAR(400) = 'red,blue,green,yellow,black'
DECLARE @separator CHAR = ','
SELECT [value] As Colour
FROM STRING_SPLIT(@stringValue, @separator);
结果：
红色 蓝色 绿色 黄色 黑色
答案 8 :(得分：2)
很晚，但是尝试一下：
np.put_along_axis所以我们有这个： tbl_Sample：
SELECT ColumnID, Column1, value --Do not change 'value' name. Leave it as it is.
FROM tbl_Sample
CROSS APPLY STRING_SPLIT(Tags, ','); --'Tags' is the name of column containing comma separated values
运行此查询后：
ColumnID| Column1 | Tags
--------|-----------|-------------
1 | ABC | 10,11,12
2 | PQR | 20,21,22
谢谢！
答案 9 :(得分：2)
我知道它有很多答案，但是我想像其他人和string_split SQL Server 2016本机函数一样编写我的split函数版本。
create function [dbo].[Split]
(
@Value nvarchar(max),
@Delimiter nvarchar(50)
)
returns @tbl table
(
Seq int primary key identity(1, 1),
Value nvarchar(max)
)
as begin
declare @Xml xml = cast('<d>' + replace(@Value, @Delimiter, '</d><d>') + '</d>' as xml)
insert into @tbl
(Value)
select a.split.value('.', 'nvarchar(max)') as Value
from @Xml.nodes('/d') a(split)
return
end
这是问题的答案。
CREATE TABLE Testdata
(
SomeID INT,
OtherID INT,
String VARCHAR(MAX)
)
INSERT Testdata SELECT 1, 9, '18,20,22'
INSERT Testdata SELECT 2, 8, '17,19'
INSERT Testdata SELECT 3, 7, '13,19,20'
INSERT Testdata SELECT 4, 6, ''
INSERT Testdata SELECT 9, 11, '1,2,3,4'
select t.SomeID, t.OtherID, s.Value
from Testdata t
cross apply dbo.Split(t.String, ',') s
--Output
SomeID OtherID Value
1 9 18
1 9 20
1 9 22
2 8 17
2 8 19
3 7 13
3 7 19
3 7 20
4 6
9 11 1
9 11 2
9 11 3
9 11 4
将Split与其他Split合并
declare @Names nvarchar(max) = 'a,b,c,d'
declare @Codes nvarchar(max) = '10,20,30,40'
select n.Seq, n.Value Name, c.Value Code
from dbo.Split(@Names, ',') n
inner join dbo.Split(@Codes, ',') c on n.Seq = c.Seq
--Output
Seq Name Code
1 a 10
2 b 20
3 c 30
4 d 40
分裂两次
declare @NationLocSex nvarchar(max) = 'Korea,Seoul,1;Vietnam,Kiengiang,0;China,Xian,0'
; with rows as
(
select Value
from dbo.Split(@NationLocSex, ';')
)
select rw.Value r, cl.Value c
from rows rw
cross apply dbo.Split(rw.Value, ',') cl
--Output
r c
Korea,Seoul,1 Korea
Korea,Seoul,1 Seoul
Korea,Seoul,1 1
Vietnam,Kiengiang,0 Vietnam
Vietnam,Kiengiang,0 Kiengiang
Vietnam,Kiengiang,0 0
China,Xian,0 China
China,Xian,0 Xian
China,Xian,0 0
拆分为列
declare @Numbers nvarchar(50) = 'First,Second,Third'
; with t as
(
select case when Seq = 1 then Value end f1,
case when Seq = 2 then Value end f2,
case when Seq = 3 then Value end f3
from dbo.Split(@Numbers, ',')
)
select min(f1) f1, min(f2) f2, min(f3) f3
from t
--Output
f1 f2 f3
First Second Third
按范围生成行
declare @Ranges nvarchar(50) = '1-2,4-6'
declare @Numbers table (Num int)
insert into @Numbers values (1),(2),(3),(4),(5),(6),(7),(8)
; with t as
(
select r.Seq, r.Value,
min(case when ft.Seq = 1 then ft.Value end) ValueFrom,
min(case when ft.Seq = 2 then ft.Value end) ValueTo
from dbo.Split(@Ranges, ',') r
cross apply dbo.Split(r.Value, '-') ft
group by r.Seq, r.Value
)
select t.Seq, t.Value, t.ValueFrom, t.ValueTo, n.Num
from t
inner join @Numbers n on n.Num between t.ValueFrom and t.ValueTo
--Output
Seq Value ValueFrom ValueTo Num
1 1-2 1 2 1
1 1-2 1 2 2
2 4-6 4 6 4
2 4-6 4 6 5
2 4-6 4 6 6
答案 10 :(得分：1)
;WITH tmp(SomeID, OtherID, DataItem, Data) as (
SELECT SomeID, OtherID, LEFT(Data, CHARINDEX(',',Data+',')-1),
STUFF(Data, 1, CHARINDEX(',',Data+','), '')
FROM Testdata
WHERE Data > ''
)
SELECT SomeID, OtherID, Data
FROM tmp
ORDER BY SomeID
只对上述查询进行微小的修改......
答案 11 :(得分：1)
使用此方法时，您必须确保没有任何值包含非法的XML - user1151923
我总是使用XML方法。确保使用VALID XML。我有两个函数可以在有效的XML和Text之间进行转换。 （我倾向于删除回车，因为我通常不需要它们。
CREATE FUNCTION dbo.udf_ConvertTextToXML (@Text varchar(MAX))
RETURNS varchar(MAX)
AS
BEGIN
SET @Text = REPLACE(@Text,CHAR(10),'')
SET @Text = REPLACE(@Text,CHAR(13),'')
SET @Text = REPLACE(@Text,'<','<')
SET @Text = REPLACE(@Text,'&','&')
SET @Text = REPLACE(@Text,'>','>')
SET @Text = REPLACE(@Text,'''',''')
SET @Text = REPLACE(@Text,'"','"')
RETURN @Text
END
CREATE FUNCTION dbo.udf_ConvertTextFromXML (@Text VARCHAR(MAX))
RETURNS VARCHAR(max)
AS
BEGIN
SET @Text = REPLACE(@Text,'<','<')
SET @Text = REPLACE(@Text,'&','&')
SET @Text = REPLACE(@Text,'>','>')
SET @Text = REPLACE(@Text,''','''')
SET @Text = REPLACE(@Text,'"','"')
RETURN @Text
END
答案 12 :(得分：1)
功能
CREATE FUNCTION dbo.SplitToRows (@column varchar(100), @separator varchar(10))
RETURNS @rtnTable TABLE
(
ID int identity(1,1),
ColumnA varchar(max)
)
AS
BEGIN
DECLARE @position int = 0
DECLARE @endAt int = 0
DECLARE @tempString varchar(100)
set @column = ltrim(rtrim(@column))
WHILE @position<=len(@column)
BEGIN
set @endAt = CHARINDEX(@separator,@column,@position)
if(@endAt=0)
begin
Insert into @rtnTable(ColumnA) Select substring(@column,@position,len(@column)-@position)
break;
end
set @tempString = substring(ltrim(rtrim(@column)),@position,@endAt-@position)
Insert into @rtnTable(ColumnA) select @tempString
set @position=@endAt+1;
END
return
END
用例
select * from dbo.SplitToRows('T14; p226.0001; eee; 3554;', ';')
或者只是具有多个结果集的选择
DECLARE @column varchar(max)= '1234; 4748;abcde; 324432'
DECLARE @separator varchar(10) = ';'
DECLARE @position int = 0
DECLARE @endAt int = 0
DECLARE @tempString varchar(100)
set @column = ltrim(rtrim(@column))
WHILE @position<=len(@column)
BEGIN
set @endAt = CHARINDEX(@separator,@column,@position)
if(@endAt=0)
begin
Select substring(@column,@position,len(@column)-@position)
break;
end
set @tempString = substring(ltrim(rtrim(@column)),@position,@endAt-@position)
select @tempString
set @position=@endAt+1;
END
答案 13 :(得分：1)
通过创建此函数（[DelimitedSplit]）来拆分字符串，您可以对SELECT执行外部应用。
CREATE FUNCTION [dbo].[DelimitedSplit]
--===== Define I/O parameters
(@pString VARCHAR(8000), @pDelimiter CHAR(1))
--WARNING!!! DO NOT USE MAX DATA-TYPES HERE! IT WILL KILL PERFORMANCE!
RETURNS TABLE WITH SCHEMABINDING AS
RETURN
--===== "Inline" CTE Driven "Tally Table" produces values from 1 up to 10,000...
-- enough to cover VARCHAR(8000)
WITH E1(N) AS (
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL
SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1 UNION ALL SELECT 1
), --10E+1 or 10 rows
E2(N) AS (SELECT 1 FROM E1 a INNER JOIN E1 b ON b.N = a.N), --10E+2 or 100 rows
E4(N) AS (SELECT 1 FROM E2 a INNER JOIN E2 b ON b.N = a.N), --10E+4 or 10,000 rows max
cteTally(N) AS (--==== This provides the "base" CTE and limits the number of rows right up front
-- for both a performance gain and prevention of accidental "overruns"
SELECT TOP (ISNULL(DATALENGTH(@pString),0)) ROW_NUMBER() OVER (ORDER BY (SELECT NULL)) FROM E4
),
cteStart(N1) AS (--==== This returns N+1 (starting position of each "element" just once for each delimiter)
SELECT 1 UNION ALL
SELECT t.N+1 FROM cteTally t WHERE SUBSTRING(@pString,t.N,1) = @pDelimiter
),
cteLen(N1,L1) AS(--==== Return start and length (for use in substring)
SELECT s.N1,
ISNULL(NULLIF(CHARINDEX(@pDelimiter,@pString,s.N1),0)-s.N1,8000)
FROM cteStart s
)
--===== Do the actual split. The ISNULL/NULLIF combo handles the length for the final element when no delimiter is found.
SELECT ItemNumber = ROW_NUMBER() OVER(ORDER BY l.N1),
Item = SUBSTRING(@pString, l.N1, l.L1)
FROM cteLen l
;
测试
CREATE TABLE #Testdata
(
SomeID INT,
OtherID INT,
String VARCHAR(MAX)
)
INSERT #Testdata SELECT 1, 9, '18,20,22'
INSERT #Testdata SELECT 2, 8, '17,19'
INSERT #Testdata SELECT 3, 7, '13,19,20'
INSERT #Testdata SELECT 4, 6, ''
INSERT #Testdata SELECT 9, 11, '1,2,3,4'
SELECT
*
FROM #Testdata
OUTER APPLY [dbo].[DelimitedSplit](String,',')
DROP TABLE #Testdata
结果
SomeID OtherID String ItemNumber Item
1 9 18,20,22 1 18
1 9 18,20,22 2 20
1 9 18,20,22 3 22
2 8 17,19 1 17
2 8 17,19 2 19
3 7 13,19,20 1 13
3 7 13,19,20 2 19
3 7 13,19,20 3 20
4 6 1
9 11 1,2,3,4 1 1
9 11 1,2,3,4 2 2
9 11 1,2,3,4 3 3
9 11 1,2,3,4 4 4
答案 14 :(得分：0)
以下适用于sql server 2008
select *, ROW_NUMBER() OVER(order by items) as row#
from
( select 134 myColumn1, 34 myColumn2, 'd,c,k,e,f,g,h,a' comaSeperatedColumn) myTable
cross apply
SPLIT (rtrim(comaSeperatedColumn), ',') splitedTable -- gives 'items' column
将使用原始表格列加上＆＃34;项目＆＃34;获取所有笛卡尔积。拆分表。
答案 15 :(得分：0)
您可以使用以下功能提取数据
CREATE FUNCTION [dbo].[SplitString]
(
@RowData NVARCHAR(MAX),
@Delimeter NVARCHAR(MAX)
)
RETURNS @RtnValue TABLE
(
ID INT IDENTITY(1,1),
Data NVARCHAR(MAX)
)
AS
BEGIN
DECLARE @Iterator INT
SET @Iterator = 1
DECLARE @FoundIndex INT
SET @FoundIndex = CHARINDEX(@Delimeter,@RowData)
WHILE (@FoundIndex>0)
BEGIN
INSERT INTO @RtnValue (data)
SELECT
Data = LTRIM(RTRIM(SUBSTRING(@RowData, 1, @FoundIndex - 1)))
SET @RowData = SUBSTRING(@RowData,
@FoundIndex + DATALENGTH(@Delimeter) / 2,
LEN(@RowData))
SET @Iterator = @Iterator + 1
SET @FoundIndex = CHARINDEX(@Delimeter, @RowData)
END
INSERT INTO @RtnValue (Data)
SELECT Data = LTRIM(RTRIM(@RowData))
RETURN
END