При попытке запустить следующую хранимую процедуру из django, я получаю OperationError (1172, «Результат состоит из более чем одной строки»). Есть идеи, что я могу делать неправильно?

-- --------------------------------------------------------------------------------
-- Routine DDL
-- Note: comments before and after the routine body will not be stored by the server
-- --------------------------------------------------------------------------------
DELIMITER $

CREATE DEFINER=`root`@`localhost` PROCEDURE `UpdatePrices`(IN storeId int, IN bottleSize VARCHAR(50))
BEGIN
    DECLARE amount DECIMAL(10,2); DECLARE isCustom INT DEFAULT 0;
    DECLARE changeType VARCHAR(50) DEFAULT 'State'; DECLARE updateType INT DEFAULT 0;

        IF bottleSize = '1000 Ml' THEN
            SELECT S1000IncreaseChoices INTO changeType FROM store_store WHERE StoreID = storeId;

            IF changeType = 'State' THEN
                SELECT updateType = 0;
            END IF;

            IF changeType = 'Flat' THEN
                SELECT S1000IncreaseAmount INTO amount FROM store_store WHERE StoreID = storeId;
                SELECT updateType = 1;
            END IF;


            IF changeType = 'Percent' THEN
                SELECT 1 - S1000IncreaseAmount/100 INTO amount FROM store_store WHERE StoreID = storeId;
                SELECT updateType = 2;
            END IF;
        END IF;

        IF updateType = 0 THEN
            update store_storeliquor SL 
            inner join liquor_liquor LL
            on liquorID_id = id
            set StorePrice = ShelfPrice
            where BottleSize = bottleSize
            and storeID_id = storeId
            and custom = 0;
        END IF;

        IF updateType = 1 THEN
            update store_storeliquor SL 
            inner join liquor_liquor LL
            on liquorID_id = id
            set StorePrice = OffPremisePrice + amount
            where BottleSize = bottleSize
            and storeID_id = storeId
            and custom = 0;
        END IF;

        IF updateType = 1 THEN
            update store_storeliquor SL 
            inner join liquor_liquor LL
            on liquorID_id = id
            set StorePrice = OffPremisePrice / amount
            where BottleSize = bottleSize
            and storeID_id = storeId
            and custom = 0;
        END IF;



END

Я не уверен, имеет ли это значение, но я запускаю хранимую процедуру следующим образом:

def priceupdate(request, store_id):

    cursor = connection.cursor()
    cursor.callproc("UpdatePrices", (store_id, '1000 ML'))
    cursor.close()
    return HttpResponseRedirect(request.META.get('HTTP_REFERER'))