我有一个这样的SQL表:

| SomeID         | OtherID     | Data
+----------------+-------------+-------------------
| abcdef-.....   | cdef123-... | 18,20,22
| abcdef-.....   | 4554a24-... | 17,19
| 987654-.....   | 12324a2-... | 13,19,20

是否有一个查询,我可以执行查询,如SELECT OtherID, SplitData where SomeID = 'abcdef-.......,返回单独的行,就像这样:

| OtherID     | SplitData
+-------------+-------------------
| cdef123-... | 18
| cdef123-... | 20
| cdef123-... | 22
| 4554a24-... | 17
| 4554a24-... | 19

基本上把我的数据在逗号处分割成单独的行?

我知道将逗号分隔的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这种方法非常有用。

我不想在应用程序中进行拆分,因为我需要分页,所以我想在重构整个应用程序之前探索选项。

它是SQL Server 2008(非r2)。


当前回答

很晚了,但是试试这个:

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

所以我们有了这个: tbl_Sample:

ColumnID|   Column1 |   Tags
--------|-----------|-------------
1       |   ABC     |   10,11,12    
2       |   PQR     |   20,21,22

运行此查询后:

ColumnID|   Column1 |   value
--------|-----------|-----------
1       |   ABC     |   10
1       |   ABC     |   11
1       |   ABC     |   12
2       |   PQR     |   20
2       |   PQR     |   21
2       |   PQR     |   22

谢谢!

其他回答

select t.OtherID,x.Kod
    from testData t
    cross apply (select Code from dbo.Split(t.Data,',') ) x

终于,SQL Server 2016结束了等待。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

所有其他方法来分割字符串,如XML, tallytable, while循环等。已经被STRING_SPLIT函数破坏了。

这里有一篇关于性能比较的优秀文章:性能惊喜和假设:STRING_SPLIT。

对于旧版本,这里使用的是一个分割字符串函数(可能的最佳方法)

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 ;

从talley引用哦!一个改进的SQL 8K“CSV分配器”函数

请参考下面的TSQL。STRING_SPLIT函数仅在兼容性级别130及更高级别下可用。

TSQL:

DECLARE @stringValue NVARCHAR(400) = 'red,blue,green,yellow,black';
DECLARE @separator CHAR = ',';

SELECT [value]  As Colour
FROM STRING_SPLIT(@stringValue, @separator); 

结果:

颜色

红色的 蓝色的 绿色 黄色的 黑色的

检查这个

 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); 

函数

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;', ';');

或者只是一个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;