string concatenation in stored procedures

[sajid kamal]

hi,

i have problem. i am wring a stored procedure in mysql for my customer sale information. i want daily sale items in one string my procedure is

-- --------------------------- my stored procedures started --------------------
CREATE PROCEDURE dbshop.`proDailySaleDetails`(IN _cID VARCHAR(5), OUT ItemDesc varchar(200) charset utf8)

BEGIN
DECLARE no_more_rows BOOLEAN;
DECLARE lSaleDesc varchar(200) charset utf8;
DECLARE _CustomerID,_eDate,_pTitle,_Packing,_SAmountType,_Qty,_Rate,_CommAmount,_TotalAmount,_RecivedAmount,_tKey varchar(100) charset utf8;
DECLARE cCustomerSaleDetails CURSOR FOR
Select tblsaledetails.CustomerID, tblsalepurchasetran.eDate, tblproducts.pTitle, tblproducts.Packing,tblproducts.SAmountType, tblsaledetails.Qty, tblsaledetails.Rate, tblsaledetails.CommAmount, tblsaledetails.TotlaAmount, ifnull(tblsaledetails.RecivedAmount,0) as RecivedAmount ,tblsaledetails.tKey From tblsalepurchasetran Inner Join tblsaledetails On tblsaledetails.sKey = tblsalepurchasetran.ID Inner Join tblproducts On tblsalepurchasetran.iID = tblproducts.ID Where(tblsaledetails.CustomerID =_cID and tblsalepurchasetran.eDate=curdate()) Order By tblsaledetails.ID;

DECLARE CONTINUE HANDLER FOR NOT FOUND
SET no_more_rows = TRUE;

OPEN cCustomerSaleDetails;

the_loop: LOOP
SET lSaleDesc=NULL;

FETCH cCustomerSaleDetails INTO _CustomerID,_eDate,_pTitle,_Packing,_SAmountType,_Qty,_Rate,_CommAmount,_TotalAmount,_RecivedAmount,_tKey;
IF no_more_rows THEN
-- CLOSE cCustomerSaleDetails;
LEAVE the_loop;
END IF;

SET ItemDesc= CONCAT('/',_pTitle ,' ',_Packing,_Qty);

END LOOP the_loop;
close cCustomerSaleDetails;
END;

-- --------------------------- my stored procedures Ended --------------------
i have many record in my tables and my procedures cursor fetch all records but when i try to concatenation record it give me null value

"i need all Item name in one string."

this line work well
SET ItemDesc= CONCAT('/',_pTitle ,' ',_Packing,_Qty);

but when am try to add other line in string
it give a null value

SET ItemDesc= CONCAT(ItemDesc,'/',_pTitle ,' ',_Packing,_Qty);

i think am am not know much about mysql and my concatenation is wrong.
please help me what i am do for correct results.