Question : Cursor Deadlock when moving items from cart to order

I just started testing my web application with real users and as the volume has picked up, i am receiving the following error once or twice a day. I am currently running at about 25% volume, so i need a solution.

Transaction (Process ID 60) was deadlocked on lock resources with another process and has been chosen as the deadlock victim. Rerun the transaction.

Here is the stored procedure that is causing this issue. Please help me optimize the cursor / add a no lock / remove cursor all together.

DECLARE @OrderNumber int,
            @Sku char(9),
            @Price decimal(16,2),
            @Qty int

SELECT @OrderNumber = SCOPE_IDENTITY()

DECLARE CartItemsCsr CURSOR FOR

      SELECT Sku, Price, Qty FROM dbo.CartItems WHERE UserID = @UserID

      OPEN CartItemsCsr
            FETCH NEXT FROM CartItemsCsr INTO @Sku, @Price, @Qty
            WHILE @@FETCH_STATUS = 0
            BEGIN

                  INSERT INTO [OrderLine]
                                    ([OrderNumber]
                               ,[Sku]
                               ,[Price]
                               ,[Qty])
                  VALUES
                               (@OrderNumber
                               ,@Sku
                               ,@Price
                               ,@Qty)

                  UPDATE Skus SET QtyOnHand = QtyOnHand - @Qty WHERE Sku = @Sku

            FETCH NEXT FROM CartItemsCsr INTO @Sku, @Price, @Qty
            END

      CLOSE CartItemsCsr
DEALLOCATE CartItemsCsr

DELETE CartItems WHERE UserID = @UserID

thanks,

Brian

Answer : Cursor Deadlock when moving items from cart to order

small update

                       
         
           
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             DECLARE @OrderNumber int,
            @Sku char(9),
            @Price decimal(16,2),
            @Qty int

SELECT @OrderNumber = SCOPE_IDENTITY()

INSERT INTO [OrderLine]
            ([OrderNumber]
         ,[Sku]
         ,[Price]
         ,[Qty])
SELECT Sku, Price, Qty FROM dbo.CartItems WHERE UserID = @UserID

UPDATE S SET QtyOnHand = QtyOnHand - CI.Qty 
FROM Skus S INNER JOIN dbo.CertItems CI ON S.Sku = CI.Sku
WHERE CI.UserID = @UserID
           
DELETE CartItems WHERE UserID = @UserID

           
         

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