Create function int select_dynamic(range varchar(255)) 

As
declare
@Qry Varchar(2000) 
Begin
	Begin try
		Set @Qry =”select * from table1 where col1 
in (“+range+”)”
		Exec @qry
	Catch
		Print “error processing parameter”
		Return -1
	End try
	
Return 1
END

you can write this query in table valued function

DECLARE @RangeValue As VARCHAR(MAX)
SET @RangeValue = '1,2,'

DECLARE @Qry As VARCHAR(MAX)

DECLARE @ResData AS VARCHAR(MAX)
DECLARE @InData AS VARCHAR(MAX)

DECLARE @rId AS INT
DECLARE @Pos AS INT

SET @ResData = ''
SET @InData = ''
WHILE(LEN(@RangeValue)>1)
BEGIN
	SET @Pos = CHARINDEX(',',@RangeValue,1)
	SET @rId = SUBSTRING(@RangeValue,1,@Pos-1)	
	SET @ResData = @ResData + CASE WHEN @ResData <> '' THEN ','
ELSE '' END + 'ISNULL(['+ CAST(@rId AS VARCHAR(5)) + '],0)
AS Range' + CAST(@rId AS VARCHAR(5))
	SET @InData = @InData + CASE WHEN @InData <> '' THEN ','
ELSE '' END + '['+ CAST(@rId AS VARCHAR(5)) + ']'
	SET @RangeValue=SUBSTRING(@RangeValue,@Pos+1,LEN(@RangeValue))
END

SET @Qry = 
'SELECT '
	+ @ResData + 
' FROM 
(
	SELECT Col1 FROM table1(NoLock)
) p
PIVOT
(
	MAX (Col1) FOR Col1 IN (' + @InData + ')
) AS pvt'

--PRINT (@Qry)
EXEC (@Qry)