[sql-server] 쉼표로 구분 된 문자열을 개별 행으로 변환

마지막으로 SQL Server 2016 에서 대기가 끝났습니다 . 그들은 문자열 분리 기능을 도입했습니다 STRING_SPLIT:

select OtherID, cs.Value --SplitData
from yourtable
cross apply STRING_SPLIT (Data, ',') cs

XML, Tally 테이블, while 루프 등과 같은 문자열을 분할하는 다른 모든 방법은이 STRING_SPLIT함수에 의해 사라졌습니다 .

여기에 성능 비교와 훌륭한 기사입니다 성능 놀라움과 가정 : STRING_SPLIT .

이전 버전의 경우 Tally Table을 사용하면 하나의 분할 문자열 함수가 있습니다 (최상의 접근 방식)

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
;

Tally OH 에서 추천 ! 향상된 SQL 8K“CSV 스플리터”기능

답변

 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); 

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

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

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); 

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

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

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

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