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ASP.NET C#: Entity updating is being blocked

Experiencing an issue about updating mysql DB through EF. It's not the first time I'm dealing with it, so I had some ideas about why isn't my data getting changed. I tried changing an element in goods array; tried editing an object, recieved through LINQ-request (seen some examples of this method); made some attempts on marking element found in the database before editing (like EntityState and Attach()). Nothing of these made any difference, so I tried removing <asp:UpdatePanel> from Site.Master to see what happens (responsive for postback blocking to prevent page shaking on update), but nothing changed (while btnRedeemEdit.IsPostBack having its default value).
Code below is the function I use for updates.
protected void btnRedeemEdit_Click(object sender, EventArgs e)
{
if (!string.IsNullOrEmpty(Request.QueryString["id"]))
{
var db = new GoodContext();
var goods = db.Goods.ToList();
Good theGood = goods.FirstOrDefault(x => x.Id == int.Parse(Request.QueryString["id"]));
//db.Goods.Attach(theGood);//No effect
//db.Entry(theGood).State = System.Data.Entity.EntityState.Modified; //No effect
if (theGood != default)
{
theGood.AmountSold = GetInput().AmountSold;
theGood.APF = GetInput().APF;
theGood.Barcode = GetInput().Barcode;
theGood.Description = GetInput().Description;
theGood.ImagesUrl = GetInput().ImagesUrl;//"https://i.pinimg.com/564x/2d/b7/d8/2db7d8c53b818ce838ad8bf6a4768c71.jpg";
theGood.Name = GetInput().Name;
theGood.OrderPrice = GetInput().OrderPrice;
theGood.Profit = GetInput().Profit;
theGood.RecievedOn = GetInput().RecievedOn;//DateTime.Parse(GetInput().RecievedOn).Date.ToString();
theGood.TotalAmount = GetInput().TotalAmount;
theGood.WeightKg = GetInput().WeightKg;
//SetGoodValues(goods[editIndex],GetInput());//Non-working
db.SaveChanges();
Response.Redirect("/AdminGoods");
}
else Response.Write($"<script>alert('Good on ID does not exist');</script>");
}
else Response.Write($"<script>alert('Unable to change: element selected does not exist');</script>");
}
Notice, that no alerts appear during execution, so object in database can be found.
Are there any more things, that can be responsible for blocking database updates?

A few things to update & check:
Firstly, DbContexts should always be disposed, so in your case wrap the DbContext inside a using statement:
using (var db = new GoodContext())
{
// ...
}
Next, there is no need to load all goods from the DbContext, just use Linq to retrieve the one you want to update:
using (var db = new GoodContext())
{
Good theGood = db.Goods.SingleOrDefault(x => x.Id == int.Parse(Request.QueryString["id"]));
if (theGood is null)
{
Response.Write($"<script>alert('Good on ID does not exist');</script>");
return;
}
}
The plausible suspect is what does "GetInput()" actually do, and have you confirmed that it actually has the changes you want? If GetInput is a method that returns an object containing your changes then it only needs to be called once rather than each time you set a property:
(Inside the using() {} scope...)
var input = GetInput();
theGood.AmountSold = input.AmountSold;
theGood.APF = input.APF;
theGood.Barcode = input.Barcode;
theGood.Description = input.Description;
// ...
db.SaveChanges();
If input has updated values but after calling SaveChanges you aren't seeing updated values in the database then there are two things to check.
1) Check that the database connection string at runtime matches the database that you are checking against. The easiest way to do that is to get the connection string from the DbContext instance's Database.
EF 6:
using (var db = new GoodContext())
{
var connectionString = db.Database.Connection.ConnectionString; // Breakpoint here and inspect.
EF Core: (5/6)
using (var db = new GoodContext())
{
var connectionString = db.Database.GetConnectionString();
Often at runtime the DbContext will be initialized with a connection string from a web.config / .exe.config file that you don't expect so you're checking one database expecting changes while the application is using a different database / server. (More common than you'd expect:)
2) Check that you aren't disabling tracking proxies. By default EF will enable change tracking which is how it knows if/when data has changed for SaveChanges to generate SQL statements. Sometimes developers will encounter performance issues and start looking for ways to speed up EF including disabling change tracking on the DbContext. (A fine option for read-only systems, but a pain for read-write)
EF6 & EF Core: (DbContext initialization)
Configuration.AutoDetectChangesEnabled = false; // If you have this set to false consider removing it.
If you must disable change tracking then you have to explicitly set the EntityState of the entity to Modified before calling SaveChanges():
db.Entry(theGood).State = EntityState.Modified;
db.SaveChanges();
Using change tracking is preferable to using EntityState because with change tracking EF will only generate an UPDATE statement if any values have changed, and only for the values that changed. With EntityState.Modified EF will always generate an UPDATE statement for all non-key fields regardless if any of them had actually changed or not.

Updating an entity with required properties in Entity Framework

I realise that updating entities without first selecting them is a common problem and many solutions are already on StackOverflow, however after reading these I'm still having a problem.
I'm using the following code to update a User entitiy:
using (var context = GetContext())
{
var userEntity = new UserEntity() { ID = userUpdate.ID };
context.Users.Attach(userEntity);
context.Entry(userEntity).CurrentValues.SetValues(userUpdate);
context.SaveChanges();
}
However this results in a DbEntityValidationException being thrown because my User entitiy has some required properties but these aren't necessarily set on the updated entity.
Is there any way around this or is it simply a case of removing the required properties?
Thanks!

I've found an answer here: Entity Framework/MVC3: temporarily disable validation
By temporarily disabling validation I can bypass the checks and insert any number of values without retrieving the required properties first:
using (var context = GetContext())
{
var userEntity = new UserEntity() { ID = userUpdate.ID };
context.Users.Attach(userEntity);
context.Entry(userEntity).CurrentValues.SetValues(userUpdate);
// Disable entity validation
context.Configuration.ValidateOnSaveEnabled = false;
context.SaveChanges();
}

If you only want to update particular fields in your entity without having to retrieve the entire thing from the database first:
var userEntity = new UserEntity() { ID = userUpdate.ID };
userEntity.SomeProperty = userUpdate.SomeProperty;
//Tell EF to only update the SomeProperty value:
context.Entry(userEntity).Property(x => x.SomeProperty).IsModified = true;
context.SaveChanges();

Entity Framework SaveChanges() not updating the database

var paymentAttempt = _auctionContext.PaymentAttempts.Where(o => o.Id == paymentAttemptId).SingleOrDefault();
if (paymentAttempt != null)
{
paymentAttempt.PaymentAttemptStatusId = (int)PaymentAttemptStatus.Defunct;
paymentAttempt.PaymentAttemptStatus = _auctionContext.PaymentAttemptStatuses.Where(pas => pas.Id == paymentAttempt.PaymentAttemptStatusId).First();
var relevantWinningBidsTotalPrices = _auctionContext.GetWinningBidsTotalPricesForPaymentAttempt(paymentAttemptId).ToArray();
foreach (var winningBid in relevantWinningBidsTotalPrices)
{
winningBid.Locked = false;
_auctionContext.UpdateObject(winningBid);
}
_auctionContext.SaveChanges();
}
In the above code after
_auctionContext.SaveChanges();
is called winningBid is updated as expected but paymentAttempt isn't. Why is this? It is really frustrating. There is no error either. I would expect a failure to occur if there was a problem like EF wasn't tracking the object or something like that, but no such error is happening.

That's because you need to pass the paymentAttempt object to your context, to let it know that it is an object that needs to be updated.
For example, assuming that _auctionContext is an instance of DbContext:
// any changes related to the paymentAttempt object
_auctionContext.Entry(paymentAttempt).State = EntityState.Modified;
foreach (var winningBid in relevantWinningBidsTotalPrices)
{
winningBid.Locked = false;
_auctionContext.UpdateObject(winningBid);
}
_auctionContext.SaveChanges();
Another option is the Attach method:
_auctionContext.Attach(paymentAttempt);
_auctionContext.ObjectStateManager.ChangeObjectState(paymentAttempt, System.Data.EntityState.Modified);

If you don't have Entry try adding:
using System.Data.Entity.Infrastructure;
using System.Data.Entity;
then you may simply use:
_auctionContext.Entry(paymentAttempt).State = EntityState.Modified;
_auctionContext.SaveChanges();

I fell on this question but for a different problem. I discovered that if you call SaveChanges() on an object that hasn't been modified, EF will not update anything. This makes sense, but I needed the DB to be updated so that other users would see that a SaveChanges() had been executed, regardless of whether any fields had changed. To force an update without changing any fields:
Dim entry As DbEntityEntry = entities.Entry(myentity)
entry.State = Entity.EntityState.Modified

I know this is late but there's another explanation worth mentioning. Even though your field name contains ID and may be set to autoincrement, be sure to verify that you declared it in your table the primary key.

Why doesn't entity framework concretize my entity's one to many relationship?

I am using a code-first approach with Entity Framework, and a repository pattern to get entities back from my database. In my data model, each OverallEvent has many EventInConcept children. I want my GetEvents method to return an IList of OverallEvents, and I want the children of the aforementioned relationship to be concretized such that they can be accessed outside my DbContext (which AssessmentSystemContext is). This is the code I currently have:
public IList<OverallEvent> GetEvents() {
using (var context = new AssessmentSystemContext()) {
return context.OverallEvents
.Select(evnt => new {
OverallEvent = evnt,
// evnt.EventsInConcept is a public virtual ICollection<EventInConcept>
ConcreteEventsInConcept = evnt.EventsInConcept
})
.AsEnumerable()
.Select(evntData => {
evntData.OverallEvent.EventsInConcept = evntData.ConcreteEventsInConcept.ToList();
// foreach (var eic in evntData.OverallEvent.EventsInConcept) {
// eic.Name = eic.Name;
// }
return evntData.OverallEvent;
})
.ToList();
}
}
It gives me back a list of OverallEvent entities, which is fine, but the trouble is that if I try to access the child relationship EventsInConcept, I get an error. For example:
EventRepository repoEvent = new EventRepository();
var gotEvents = repoEvent.GetEvents();
var firstEventInConcept = gotEvents[0].EventsInConcept.FirstOrDefault();
... gives me the error "The ObjectContext instance has been disposed and can no longer be used for operations that require a connection."
I understood from the answer to an earlier question that if I projected EventsInConcept into a wrapper object, then explicitly set it in a later .Select call (ie. evntData.OverallEvent.EventsInConcept = evntData.ConcreteEventsInConcept.ToList();), it would concretize this one:many relationship and I would be able to access EventsInConcept outside of the DbContext, but it isn't working here. Note that if I uncomment the foreach loop, it starts working, so to get it to work I have to explicitly set a property on every single entry of EventsInConcept. I don't really want to have to do this (I'm picking an arbitrary property, .Name, which feels wrong anyway). Is there a better way?

Disable lazy loading for this query. It is of no use in that situation and when you dispose the context after the entities have been retrieved:
public IList<OverallEvent> GetEvents() {
using (var context = new AssessmentSystemContext()) {
context.Configuration.LazyLoadingEnabled = false;
return ...
}
}
It might be possible that EF doesn't recognize that the collection has been loaded when you use a projection (instead of eager or explicit loading) and triggers lazy loading as soon as you access the collection.

Updating Database via Anonymous Type?

The following code gets all the rows from my Activities table that have not already been posted on Twitter. It then loops through and posts Twitter updates for each of those row. In the process, I would like to update the database to indicate these rows have now been "twittered".
However, I'm getting an error (indicated below) when I try and update this value. I assume this is because I'm using an anonymous type. However, if I use the full type, that will require pulling a lot of unnecessary data from the database.
Is there a way to accomplish this efficiently? Or is this yet another case where EF forces me to make compromises in performance?
using (MyEntities context = new MyEntities())
{
var activities = from act in context.Activities
where act.ActTwittered == false
select new { act.ActID, act.ActTitle, act.Category,
act.ActDateTime, act.Location, act.ActTwittered };
foreach (var activity in activities)
{
twitter.PostUpdate("...");
activity.ActTwittered = true; // <== Error: ActTwittered is read-only
}
}

You could try a "fake object approach" like this:
using (MyEntities context = new MyEntities())
{
var activities = from act in context.Activities
where act.ActTwittered == false
select new { act.ActID, act.ActTitle, act.Category,
act.ActDateTime, act.Location, act.ActTwittered };
foreach (var activity in activities)
{
twitter.PostUpdate("...");
// Create fake object with necessary primary key
var act = new Activity()
{
ActID = activity.ActID,
ActTwittered = false
};
// Attach to context -> act is in state "Unchanged"
// but change-tracked now
context.Activities.Attach(act);
// Change a property -> act is in state "Modified" now
act.ActTwittered = true;
}
// all act are sent to server with sql-update statements
// only for the ActTwittered column
context.SaveChanges();
}
It's "theoretical" code, not sure if it would work.
Edit
Not "theoretical" anymore. I've tested this with DbContext of EF 4.1 and it works as described in the sample code above. (Because DbContext is only a wrapper API around ObjectContext it's almost safe to assume that it also will work in EF 4.0.)

If you simply select 'act', then it should work. Don't forget to submit after editing.

Why are you calling select new instead of returning entire object. Entity framework will only be able to update property if it is correctly defined in schema resources which certainly is not case with anonymous type.
Entity framework will never be able to determine which table and which field the property is mapped to.