【Sql】改where條件In為使用表值函數

CREATE FUNCTION [dbo].[fn_StrSplit](@str VARCHAR(8000), @Separator VARCHAR(10))
RETURNS @re TABLE(FID VARCHAR(100))
AS
BEGIN
DECLARE @l INT, @i INT
SELECT @i = LEN(@Separator), @l = LEN(@str)
;with cte as
(
select 0 a, 1 b union all
select b, charindex(@Separator, @str, b) + @i
from cte where b > a
)
insert into @re select substring(@str,a, case when b > @i then b-a-@i else @l - a + 1 end) value
from cte where a >0 option (maxrecursion 4000)
RETURN
end


GO

　具體的使用方法為

例： 

SELECT * FROM TABLE1 WHERE FID IN (1,2,3)

改為

SELECT * FROM TABLE1 T

JOIN fn_StrSplit('1,2,3',',') T1 ON T.FID = T1.FID