Nopcommerce update customise table when check out - model-view-controller

Question

I am newbie for nopcommerce.
Any Idea to check and update customise table when check out?
My case is like that:
I have create a new table name as "DailyLimit" table in my db.
Table field have ID,Date,DailyLimit.
when checkout product, I need to check the "Date" of Daily limit. If daily limit <= 0, then it will pop-up a alert, else it will update to DailyLimit field.
PS：I already create a date checkout attribute and make it as session.
For the Checkout controller I have add the availableQty variable pass to model.
public ActionResult OnePageCheckout(){
//validation
var cart = _workContext.CurrentCustomer.ShoppingCartItems
.Where(sci => sci.ShoppingCartType == ShoppingCartType.ShoppingCart)
.LimitPerStore(_storeContext.CurrentStore.Id)
.ToList();
//Problem here
var availableQtyFromDB = "SELECT DailyLimit FROM deliveryTbl WHERE date =Session["DeliveryDateForDesley"]" //problem here
if (cart.Count == 0)
return RedirectToRoute("ShoppingCart");
if (!_orderSettings.OnePageCheckoutEnabled)
return RedirectToRoute("Checkout");
if ((_workContext.CurrentCustomer.IsGuest() && !_orderSettings.AnonymousCheckoutAllowed))
return new HttpUnauthorizedResult();
var model = new OnePageCheckoutModel
{
ShippingRequired = cart.RequiresShipping(),
DisableBillingAddressCheckoutStep = _orderSettings.DisableBillingAddressCheckoutStep,
availableQty = availableQtyFromDB
};
return View(model);
}
But I have no idea how to write the how to SELECT statement in this controller.
And no idea how to update the daily limit.

Answer 1

Interesting question. Based on your code, I assume you haven't worked much with EF framework. when i started working with nopcommerce, i was like that too. But best thing in nopcommerce is most of common problems were solved in somewhere other part of the application.
First, blindly writing SQL in controller wont help much. Good way to learn is to have a look at
.LimitPerStore(_storeContext.CurrentStore.Id)
Method and how they have done the query/selection using Entity framework. They have done that for per store. You need to do it per day. That will help you to alight your solution in line with nopcommerce architecture.
Source: Ex-nopCommerce Developer for 3 years.