I have been able to use multi-value parameters in a report and pass them to a stored procedure without doing any heavy lifting like this. You need to create a split function shown below and use the function and the IN statement in the WHERE clause and your done.

Report Parameter

Name: FilterRegionId

Data type: Integer

Prompt: FilterRegionId

Hidden: unchecked

Internal: unchecked

Multi-value: checked

Allow null value: unchecked

Allow blank value: checked (disabled checkbox)

Available values: Non-queried

Default values: Non-queried

Stored Procedure

Parameter: @FilterRegionId AS varchar(max)

WHERE Clause: WHERE ORG.OrganizationId IN(SELECT Item FROM dbo.Split(ISNULL(@FilterRegionId, ORG.OrganizationId), ','))

Split Function

------------------------

CREATE FUNCTION [dbo].[Split]

/* This function is used to split up multi-value parameters */

(

@ItemList NVARCHAR(4000),

@delimiter CHAR(1)

)

RETURNS @IDTable TABLE (Item VARCHAR(50))

AS

BEGIN

DECLARE @tempItemList NVARCHAR(4000)

SET @tempItemList = @ItemList

DECLARE @i INT

DECLARE @Item NVARCHAR(4000)

SET @tempItemList = REPLACE (@tempItemList, @delimiter + ' ', @delimiter)

SET @i = CHARINDEX(@delimiter, @tempItemList)

WHILE (LEN(@tempItemList) > 0)

BEGIN

IF @i = 0

SET @Item = @tempItemList

ELSE

SET @Item = LEFT(@tempItemList, @i - 1)

INSERT INTO @IDTable(Item) VALUES(@Item)

IF @i = 0

SET @tempItemList = ''

ELSE

SET @tempItemList = RIGHT(@tempItemList, LEN(@tempItemList) - @i)

SET @i = CHARINDEX(@delimiter, @tempItemList)

END

RETURN

END