Using comma separated value parameter strings in SQL IN clauses
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO
CREATE FUNCTION [dbo].[CSVToTable] (@InStr VARCHAR(MAX))
RETURNS @TempTab TABLE
(id int not null)
AS
BEGIN
;-- Ensure input ends with comma
SET @InStr = REPLACE(@InStr + ',', ',,', ',')
DECLARE @SP INT
DECLARE @VALUE VARCHAR(1000)
WHILE PATINDEX('%,%', @INSTR ) <> 0
BEGIN
SELECT @SP = PATINDEX('%,%',@INSTR)
SELECT @VALUE = LEFT(@INSTR , @SP - 1)
SELECT @INSTR = STUFF(@INSTR, 1, @SP, '')
INSERT INTO @TempTab(id) VALUES (@VALUE)
END
RETURN
END
GO
This creates a user function that takes a comma separated value string and converts it into a table that SQL does understand - just pass it the sting, and it works it all out. It's pretty obvious how it works, the only complexity is the REPLACE part which ensures the string is terminated with a single comma by appending one, and removing all double commas from the string. Without this, while loop becomes harder to process, as the final number might or might not have a terminating comma and that would have to be dealt with separately.
DECLARE @LIST VARCHAR(200)
SET @LIST = '1,3'
SELECT Id, Descr FROM CSVDemo WHERE Id IN (SELECT * FROM dbo.CSVToTable(@LIST))
Comments
Post a Comment