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T-SQL中的拆分函数等价物?

  •  120
  • jinsungy  · 技术社区  · 17 年前

    我希望将“1,2,3,4,5,6,7,8,9,10,11,12,13,14,15…”(逗号分隔)拆分为表或表变量。

    15 回复  |  直到 7 年前
        1
  •  60
  •   KthProg    11 年前

    试试这个

    DECLARE @xml xml, @str varchar(100), @delimiter varchar(10)
    SET @str = '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15'
    SET @delimiter = ','
    SET @xml = cast(('<X>'+replace(@str, @delimiter, '</X><X>')+'</X>') as xml)
    SELECT C.value('.', 'varchar(10)') as value FROM @xml.nodes('X') as X(C)
    

    DECLARE @str varchar(100), @delimiter varchar(10)
    SET @str = '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15'
    SET @delimiter = ','
    ;WITH cte AS
    (
        SELECT 0 a, 1 b
        UNION ALL
        SELECT b, CHARINDEX(@delimiter, @str, b) + LEN(@delimiter)
        FROM CTE
        WHERE b > a
    )
    SELECT SUBSTRING(@str, a,
    CASE WHEN b > LEN(@delimiter) 
        THEN b - a - LEN(@delimiter) 
        ELSE LEN(@str) - a + 1 END) value      
    FROM cte WHERE a > 0
    

    How to split comma delimited string?

        2
  •  54
  •   XOR    17 年前

    这是一个有点过时的解决方案:

    /*
        Splits string into parts delimitered with specified character.
    */
    CREATE FUNCTION [dbo].[SDF_SplitString]
    (
        @sString nvarchar(2048),
        @cDelimiter nchar(1)
    )
    RETURNS @tParts TABLE ( part nvarchar(2048) )
    AS
    BEGIN
        if @sString is null return
        declare @iStart int,
                @iPos int
        if substring( @sString, 1, 1 ) = @cDelimiter 
        begin
            set @iStart = 2
            insert into @tParts
            values( null )
        end
        else 
            set @iStart = 1
        while 1=1
        begin
            set @iPos = charindex( @cDelimiter, @sString, @iStart )
            if @iPos = 0
                set @iPos = len( @sString )+1
            if @iPos - @iStart > 0          
                insert into @tParts
                values  ( substring( @sString, @iStart, @iPos-@iStart ))
            else
                insert into @tParts
                values( null )
            set @iStart = @iPos+1
            if @iStart > len( @sString ) 
                break
        end
        RETURN
    
    END
    

        3
  •  30
  •   Martin Smith    10 年前

    您已经标记了此SQL Server 2008,但此问题的未来访问者(使用SQL Server 2016+)可能希望了解 STRING_SPLIT

    有了这个新的内置函数,您现在可以直接使用

    SELECT TRY_CAST(value AS INT)
    FROM   STRING_SPLIT ('1,2,3,4,5,6,7,8,9,10,11,12,13,14,15', ',') 
    

    该功能的一些限制和性能测试的一些有希望的结果在本文中给出 this blog post by Aaron Bertrand .

        4
  •  13
  •   Todd    15 年前

    对于熟悉该功能的人来说,这与.NET非常相似:

    CREATE FUNCTION dbo.[String.Split]
    (
        @Text VARCHAR(MAX),
        @Delimiter VARCHAR(100),
        @Index INT
    )
    RETURNS VARCHAR(MAX)
    AS BEGIN
        DECLARE @A TABLE (ID INT IDENTITY, V VARCHAR(MAX));
        DECLARE @R VARCHAR(MAX);
        WITH CTE AS
        (
        SELECT 0 A, 1 B
        UNION ALL
        SELECT B, CONVERT(INT,CHARINDEX(@Delimiter, @Text, B) + LEN(@Delimiter))
        FROM CTE
        WHERE B > A
        )
        INSERT @A(V)
        SELECT SUBSTRING(@Text,A,CASE WHEN B > LEN(@Delimiter) THEN B-A-LEN(@Delimiter) ELSE LEN(@Text) - A + 1 END) VALUE      
        FROM CTE WHERE A >0
    
        SELECT      @R
        =           V
        FROM        @A
        WHERE       ID = @Index + 1
        RETURN      @R
    END
    
    SELECT dbo.[String.Split]('121,2,3,0',',',1) -- gives '2'
    
        5
  •  10
  •   Anderson Pimentel    9 年前

    这是你问的拆分函数

    CREATE FUNCTION [dbo].[split](
              @delimited NVARCHAR(MAX),
              @delimiter NVARCHAR(100)
            ) RETURNS @t TABLE (id INT IDENTITY(1,1), val NVARCHAR(MAX))
            AS
            BEGIN
              DECLARE @xml XML
              SET @xml = N'<t>' + REPLACE(@delimited,@delimiter,'</t><t>') + '</t>'
    
              INSERT INTO @t(val)
              SELECT  r.value('.','varchar(MAX)') as item
              FROM  @xml.nodes('/t') as records(r)
              RETURN
            END
    

    像这样执行函数

    select * from dbo.split('1,2,3,4,5,6,7,8,9,10,11,12,13,14,15',',')
    
        6
  •  5
  •   Charlie    12 年前
    DECLARE
        @InputString NVARCHAR(MAX) = 'token1,token2,token3,token4,token5'
        , @delimiter varchar(10) = ','
    
    DECLARE @xml AS XML = CAST(('<X>'+REPLACE(@InputString,@delimiter ,'</X><X>')+'</X>') AS XML)
    SELECT C.value('.', 'varchar(10)') AS value
    FROM @xml.nodes('X') as X(C)
    

    这一答复的来源: http://sqlhint.com/sqlserver/how-to/best-split-function-tsql-delimited

        7
  •  3
  •   Irawan Soetomo    17 年前

    我很想挤出我最喜欢的解决办法。结果表将由2列组成:PosIdx表示找到的整数的位置;和整数形式的值。

    
    create function FnSplitToTableInt
    (
        @param nvarchar(4000)
    )
    returns table as
    return
        with Numbers(Number) as 
        (
            select 1 
            union all 
            select Number + 1 from Numbers where Number < 4000
        ),
        Found as
        (
            select 
                Number as PosIdx,
                convert(int, ltrim(rtrim(convert(nvarchar(4000), 
                    substring(@param, Number, 
                    charindex(N',' collate Latin1_General_BIN, 
                    @param + N',', Number) - Number))))) as Value
            from   
                Numbers 
            where  
                Number <= len(@param)
            and substring(N',' + @param, Number, 1) = N',' collate Latin1_General_BIN
        )
        select 
            PosIdx, 
            case when isnumeric(Value) = 1 
                then convert(int, Value) 
                else convert(int, null) end as Value 
        from 
            Found
    

    它使用递归CTE作为位置列表,默认情况下从1到100。如果需要处理长度超过100的字符串,只需使用“option(maxrecursion 4000)”调用此函数,如下所示:

    
    select * from FnSplitToTableInt
    (
        '9, 8, 7, 6, 5, 4, 3, 2, 1, 0, ' + 
        '9, 8, 7, 6, 5, 4, 3, 2, 1, 0, ' +
        '9, 8, 7, 6, 5, 4, 3, 2, 1, 0, ' +
        '9, 8, 7, 6, 5, 4, 3, 2, 1, 0, ' +
        '9, 8, 7, 6, 5, 4, 3, 2, 1, 0'
    ) 
    option (maxrecursion 4000)
    
        8
  •  3
  •   Reza    12 年前
    CREATE FUNCTION Split
    (
      @delimited nvarchar(max),
      @delimiter nvarchar(100)
    ) RETURNS @t TABLE
    (
    -- Id column can be commented out, not required for sql splitting string
      id int identity(1,1), -- I use this column for numbering splitted parts
      val nvarchar(max)
    )
    AS
    BEGIN
      declare @xml xml
      set @xml = N'<root><r>' + replace(@delimited,@delimiter,'</r><r>') + '</r></root>'
    
      insert into @t(val)
      select
        r.value('.','varchar(max)') as item
      from @xml.nodes('//root/r') as records(r)
    
      RETURN
    END
    GO
    

    用法

    Select * from dbo.Split(N'1,2,3,4,6',',')
    
        9
  •  3
  •   Michał Turczyn    8 年前

    这个简单的CTE将提供所需的:

    DECLARE @csv varchar(max) = '1,2,3,4,5,6,7,8,9,10,11,12,13,14,15';
    --append comma to the list for CTE to work correctly
    SET @csv = @csv + ',';
    --remove double commas (empty entries)
    SET @csv = replace(@csv, ',,', ',');
    WITH CteCsv AS (
        SELECT CHARINDEX(',', @csv) idx, SUBSTRING(@csv, 1, CHARINDEX(',', @csv) - 1) [Value]
        UNION ALL
        SELECT CHARINDEX(',', @csv, idx + 1), SUBSTRING(@csv, idx + 1, CHARINDEX(',', @csv, idx + 1) - idx - 1) FROM CteCsv
        WHERE CHARINDEX(',', @csv, idx + 1) > 0
    )
    
    SELECT [Value] FROM CteCsv
    
        10
  •  2
  •   Scormer    12 年前

    这是另一个没有任何限制的版本(例如:使用xml方法时的特殊字符,CTE方法中的记录数),并且基于对10M+记录(源字符串平均长度为4000)的测试,它的运行速度要快得多。希望这能有所帮助。

    Create function [dbo].[udf_split] (
        @ListString nvarchar(max),
        @Delimiter  nvarchar(1000),
        @IncludeEmpty bit) 
    Returns @ListTable TABLE (ID int, ListValue nvarchar(1000))
    AS
    BEGIN
        Declare @CurrentPosition int, @NextPosition int, @Item nvarchar(max), @ID int, @L int
        Select @ID = 1,
       @L = len(replace(@Delimiter,' ','^')),
                @ListString = @ListString + @Delimiter,
                @CurrentPosition = 1 
        Select @NextPosition = Charindex(@Delimiter, @ListString, @CurrentPosition)
       While @NextPosition > 0 Begin
       Set  @Item = LTRIM(RTRIM(SUBSTRING(@ListString, @CurrentPosition, @NextPosition-@CurrentPosition)))
       If      @IncludeEmpty=1 or LEN(@Item)>0 Begin 
         Insert Into @ListTable (ID, ListValue) Values (@ID, @Item)
         Set @ID = @ID+1
       End
       Set  @CurrentPosition = @NextPosition+@L
       Set  @NextPosition = Charindex(@Delimiter, @ListString, @CurrentPosition)
      End
        RETURN
    END
    
        11
  •  1
  •   Pரதீப்    9 年前

    使用 下面是Jeff Moden的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
    ;
    

    引自 Tally OH! An Improved SQL 8K “CSV Splitter” Function

        12
  •  0
  •   kzfabi    13 年前

    This blog 在T-SQL中使用XML提供了一个非常好的解决方案。

    这是我根据该博客提出的函数(根据需要更改函数名和结果类型):

    SET ANSI_NULLS ON
    GO
    SET QUOTED_IDENTIFIER ON
    GO
    CREATE FUNCTION [dbo].[SplitIntoBigints]
    (@List varchar(MAX), @Splitter char)
    RETURNS TABLE 
    AS
    RETURN 
    (
        WITH SplittedXML AS(
            SELECT CAST('<v>' + REPLACE(@List, @Splitter, '</v><v>') + '</v>' AS XML) AS Splitted
        )
        SELECT x.v.value('.', 'bigint') AS Value
        FROM SplittedXML
        CROSS APPLY Splitted.nodes('//v') x(v)
    )
    GO
    
        13
  •  0
  •   Metaphor    13 年前
    CREATE Function [dbo].[CsvToInt] ( @Array varchar(4000)) 
    returns @IntTable table 
    (IntValue int)
    AS
    begin
    declare @separator char(1)
    set @separator = ','
    declare @separator_position int 
    declare @array_value varchar(4000) 
    
    set @array = @array + ','
    
    while patindex('%,%' , @array) <> 0 
    begin
    
    select @separator_position = patindex('%,%' , @array)
    select @array_value = left(@array, @separator_position - 1)
    
    Insert @IntTable
    Values (Cast(@array_value as int))
    select @array = stuff(@array, 1, @separator_position, '')
    end
    
        14
  •  0
  •   Andriy M    12 年前
    /* *Object:  UserDefinedFunction [dbo].[Split]    Script Date: 10/04/2013 18:18:38* */
    SET ANSI_NULLS ON
    GO
    SET QUOTED_IDENTIFIER ON
    GO
    ALTER FUNCTION [dbo].[Split]
    (@List varchar(8000),@SplitOn Nvarchar(5))
    RETURNS @RtnValue table
    (Id int identity(1,1),Value nvarchar(100))
    AS
    BEGIN
        Set @List = Replace(@List,'''','')
        While (Charindex(@SplitOn,@List)>0)
        Begin
    
        Insert Into @RtnValue (value)
        Select
        Value = ltrim(rtrim(Substring(@List,1,Charindex(@SplitOn,@List)-1)))
    
        Set @List = Substring(@List,Charindex(@SplitOn,@List)+len(@SplitOn),len(@List))
        End
    
        Insert Into @RtnValue (Value)
        Select Value = ltrim(rtrim(@List))
    
        Return
    END
    go
    
    Select *
    From [Clv].[Split] ('1,2,3,3,3,3,',',')
    GO
    
        15
  •  0
  •   Sebastian SEO    5 年前

    这对我很有用 https://www.sqlshack.com/the-string-split-function-in-sql-server/

    您应该只记得在from之后使用string_split。

    DROP TABLE IF EXISTS #Countries
    GO
    DROP TABLE IF EXISTS #CityList
    GO
    CREATE TABLE #Countries
    (Continent VARCHAR(100),
    Country VARCHAR(100))
    GO
    CREATE TABLE #CityList
    (Country VARCHAR(100),
    City VARCHAR(5000))
    GO
    INSERT INTO  #Countries
    VALUES('Europe','France'),('Europe','Germany') 
     
    INSERT INTO #CityList
    VALUES('France','Paris,Marsilya,Lyon,Lille,Nice'), ('Germany','Berlin,Hamburg,Munih,Frankfurt,Koln')
     
    SELECT 
    CN.Continent,CN.Country,value
    FROM #CityList CL CROSS APPLY string_split(CL.City,',')  INNER JOIN 
    #Countries CN ON  CL.Country = CN.Country
     
     
    DROP TABLE IF EXISTS #Countries
    GO
    DROP TABLE IF EXISTS #CityList