fn_varchar_to_table.sql

CREATE FUNCTION [dbo].[VarcharToTable] (@InStr NVARCHAR(MAX))
RETURNS @TempTab TABLE
   (id UNIQUEIDENTIFIER NOT NULL)
AS
BEGIN
    ;-- Ensure input ends with comma
    SET @InStr = REPLACE(@InStr + ',', ',,', ',')
    DECLARE @SP INT
    DECLARE @VALUE NVARCHAR(MAX)
    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

DECLARE @LIST NVARCHAR(MAX)
SET @LIST = '973150D4-0D5E-4AD0-87E1-037B9D4FC03B,973150d4-0d5e-4ad0-87e1-037b9d4fc03c'
SELECT Id, Descr FROM TableA WHERE Id IN (SELECT * FROM dbo.VarcharToTable(@LIST))