我完全同意那些抱怨这类数据的人。然而,事实是我们通常无法控制来源的格式。
这是我的方法...
首先,您需要一个标记器。这个效率很高(可能是最快的非 CLR)。见http://www.sqlservercentral.com/articles/Tally+Table/72993/
CREATE FUNCTION [dbo].[DelimitedSplit8K]
--===== 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, 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
;
GO
然后你像这样消费它......
DECLARE @Wtf VARCHAR(1000) = '1!1,3!0,23!0,288!0,340!0,521!0,24!0,38!0,26!0,27!0,281!0,19!0,470!0,568!0,601!0,2!1,251!0,7!2,140!0,285!0,11!2,33!0'
SELECT LEFT(Item, CHARINDEX('!', Item)-1)
,RIGHT(Item, CHARINDEX('!', REVERSE(Item))-1)
FROM [dbo].[DelimitedSplit8K](@Wtf, ',')
发布的函数和解析逻辑当然可以集成到一个函数中。