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Entity Framework Still Cache Although Use "Using"

I am trying to use Entity Framework for work with database, I use Extension Method and pass Entity Context Into Logic Codes, The Database is update successful, but when I call back, result, I still old Records, I guess that issue on Cache of Entities, But It not make clear, I could not find any thing wrong in my code. Please help:
Extension method:
public static bool UpdateTruck(this Truck Truck, Truck updateInfo, Entities entities)
{
var isSuccess = true;
try
{
// Find Enity Object
var ObjectModel = entities.Truck.Where(x => x.Code == Truck.Code && x.CodePlant == Truck.CodePlant).FirstOrDefault();
// Mapping Modified Properties
ObjectModel = Mapper.Map(updateInfo, ObjectModel);
// Create Database Entity Transaction
entities.Truck.AddOrUpdate(ObjectModel);
//Save Changes
entities.SaveChanges();
}
catch (Exception exception)
{
Debug.WriteLine("[Application Exception:] " + exception.Message);
isSuccess = false;
}
return isSuccess;
}
Here is where I call: if (truckInfo.FindTruck(entities).UpdateTruck(truckInfo,entities))
After that, i checked database, i value update success update, but when I call:
using (Entities entities = new Entities())
{
PageModel.Truck= Truck.FindTruck(entities);
....
It receive old record.

Entity Framework caches objects internally in a DbContext instance.
Look here

Your issue isn't caching. You are using the AddOrUpdate method, which is only designed for use when initialising a database with seed data.
Use:
entities.Truck.Attach(Truck); // if it already exists.
// since you are loading it again for some reason
var ObjectModel = entities.Truck.Where(x => x.Code == Truck.Code && x.CodePlant == Truck.CodePlant).FirstOrDefault();
// Mapping Modified Properties
ObjectModel = Mapper.Map(updateInfo, ObjectModel); // this looks dubious
// You've just loaded it from the context so it's tracked, so you could just save it
entities.SaveChanges();

C# - how to delete row in realm - android xamarin

i tried this method that I created but it prompts me an error:
Realms.RealmInvalidObjectException:This object is detached. Was it deleted from the realm?'
public void deleteFromDatabase(List<CashDenomination> denom_list)
{
using (var transaction = Realm.GetInstance(config).BeginWrite())
{
Realm.GetInstance(config).Remove(denom_list[0]);
transaction.Commit();
}
}
what is the proper coding for deleting records from database in realm in C# type of coding?

You are doing it the right way. The error message you are getting indicates that the object was removed already. Are you sure it still exists in the realm?
UPDATE:
I decided to update this answer because my comment on the other answer was a bit hard to read.
Your original code should work fine. However, if you want deleteFromDatabase to accept lists with CashDenomination instances that either have been removed already or perhaps were never added to the realm, you would need to add a check. Furthermore, note that you should hold on to your Realm instance and use it in the transaction you created. In most cases, you want to keep it around even longer, though there is little overhead to obtaining it via GetInstance.
public void deleteFromDatabase(List<CashDenomination> denom_list)
{
if (!denom_list[0].IsValid) // If this object is not in the realm, do nothing.
return;
var realm = Realm.GetInstance(config);
using (var transaction = realm.BeginWrite())
{
realm.Remove(denom_list[0]);
transaction.Commit();
}
}
Now, if you want to use identifiers, you could look it up like you do, but still just use Remove:
public void deleteFromDatabase(int denom_id)
{
var realm = Realm.GetInstance(config);
var denom = realm.All<CashDenomination>().FirstOrDefault(c => c.denom_id == denom_id);
if (denom == null) // If no entry with this id exists, do nothing.
return;
using (var transaction = realm.BeginWrite())
{
realm.Remove(denom);
transaction.Commit();
}
}
Finally, if your CashDenomination has denom_id marked as PrimaryKey, you could look it up like this:
public void deleteFromDatabase(int denom_id)
{
var realm = Realm.GetInstance(config);
var denom = realm.ObjectForPrimaryKey<CashDenomination>(denom_id);
if (denom == null) // If no entry with this id exists, do nothing.
return;
using (var transaction = realm.BeginWrite())
{
realm.Remove(denom);
transaction.Commit();
}
}

public void deleteFromDatabase(Realm realm, long cashDenominatorId)
{
realm.Write(() =>
{
var cashDenominator = realm.All<Person>().Where(c => c.Id == cashDenominatorId);
Realm.RemoveRange<CashDenomination>(((RealmResults<CashDenomination>)cashDenominator));
});
}
Which you would call as
Realm realm = Realm.GetInstance(config);
var denom_list = ...
// ...
deleteFromDatabase(realm, denom_list[0].id);

I already made it having this code :) thanks to #EpicPandaForce 's answer.
public void deleteFromDatabase(int denom_ID, int form_ID)
{
//Realm realm;
//and
//RealmConfiguration config = new RealmConfiguration(dbPath, true);
//was initialized at the top of my class
realm = Realm.GetInstance(config);
realm.Write(() =>
{
var cashflow_denom = realm.All<CashDenomination>().Where(c => c.denom_id == denom_ID);
var cashflow_form = realm.All<CashForm>().Where(c => c.form_id == form_ID);
realm.RemoveRange(((RealmResults<CashDenomination>)cashflow_denom));
realm.RemoveRange(((RealmResults<CashForm>)cashflow_form));
});
}
it is now deleting my data without exception :)

Add or Update a Record?

I have an MVC application with the following code in the POST method of the controller. I am doing an EF Add and obviously that is not right. I want it to add the record if it doesn't exist, otherwise Update. How can I do that please?
try
{
AttributeEntities db = new AttributeEntities();
IEnumerable<string> items = viewModel.SelectedAttributes2;
int i = 0;
foreach (var item in items)
{
var temp = item;
// Save it
SelectedHarmonyAttribute attribute = new SelectedHarmonyAttribute();
attribute.CustomLabel = viewModel.ItemCaptionText;
attribute.IsVisible = viewModel.Isselected;
string harmonyAttributeID = item.Substring(1, 1);
// attribute.OrderNumber = Convert.ToInt32(order);
attribute.OrderNumber = i++;
attribute.HarmonyAttribute_ID = Convert.ToInt32(harmonyAttributeID);
db.SelectedHarmonyAttributes.Add(attribute);
db.SaveChanges();
}
}

You would need to check the database for the record you are trying to add/update. If the look-up returns null, that means that it doesn't exist in the database. If it does, you can modify the record that you looked up and call db.SaveChanges() to persist the changes you made to the database.
Edit:
int id = Convert.ToInt32(harmonyAttributeID);
var existingEntry = db.SelectedHarmonyAttributes.SingleOrDefault(x => x.HarmonyAttribute_ID == id);

One common way to determine an add or update is by simply looking at an identifier field, and setting the appropriate state.
using System.Data;
SelectedHarmonyAttribute attribute;
using (var db = new YourDbContext())
{
db.Entry(attribute).State = attribute.HarmonyAttribute_ID == 0 ? EntityState.Added : EntityState.Modified;
db.SaveChanges();
}

You could import the System.Data.Entity.Migrations namespace and use the AddOrUpdate extension method:
db.SelectedHarmonyAttributes.AddOrUpdate(attribute);
db.SaveChanges();
EDIT:
I'm assuming that SelectedHarmonyAttributes is of type DbSet
EDIT2:
Only drawback with doing it this way (and it may not be a concern for you), is that your entity isn't responsible for it's own state change. This means that you can update any property of the entity to something invalid, where you might want to internally validate it on the entity itself or maybe do some other processing you always want to occur on update. If these things are a concern for you, you should add a public Update method onto the entity and check for its existence on the database first. e.g:
var attribute = db.SelectedHarmonyAttributes.SingleOrDefault(x => x.HarmonyAttribute_ID == harmonyAttributeID);
if (attribute != null)
{
attribute.Update(viewModel.ItemCaptionText, viewModel.Isselected, i++);
}
else
{
attribute = new Attribute(viewModel.ItemCaptionText, viewModel.Isselected);
db.SelectedHarmonyAttributes.Add(attribute);
}
db.SaveChanges();
Your update method might look something like:
public void Update(string customLabel, bool isVisible, int orderNumber)
{
if (!MyValidationMethod())
{
throw new MyCustomException();
}
CustomLabel = customLabel;
IsVisible = isVisible;
OrderNumber = orderNumber;
PerformMyAdditionalProcessingThatIAlwaysWantToHappen();
}
Then make all of the entities' properties public "get" but protected "set" so they can't be updated from outside the entity itself. This might be going off an a bit of a tangent but using the AddOrUpdate method would assume you don't want to control the way an update occurs and protect your domain entity from getting into an invalid state etc. Hope this helps!

Enity Framework updating with a child table causing errors

I have the following update function
public void UpdateBatchDefinition(BatchDefinition batchToUpdate)
{
if (batchToUpdate == null)
{
throw new ArgumentNullException("batchToUpdate");
}
BatchDefinition foundDefinition =
this.context.BatchDefinitions.SingleOrDefault(definition => definition.Id == batchToUpdate.Id);
if (foundDefinition != null)
{
if (!string.IsNullOrWhiteSpace(batchToUpdate.Name))
{
foundDefinition.Name = batchToUpdate.Name;
}
if (!string.IsNullOrWhiteSpace(batchToUpdate.Description))
{
foundDefinition.Description = batchToUpdate.Description;
}
if (!string.IsNullOrWhiteSpace(batchToUpdate.LoadType))
{
foundDefinition.LoadType = batchToUpdate.LoadType;
}
if (batchToUpdate.JobId != Guid.Empty)
{
foundDefinition.JobId = batchToUpdate.JobId;
}
foundDefinition.Tables = batchToUpdate.Tables;
this.context.SaveChanges();
}
}
the issue I am having Is when I am trying to update the Tables list. Tables is a List of Table and Table is a Entity of another table
Tables could be added to, removed from or left alone. I need to update that with what ever is being passed in
when I run this right now I get an 'EntityValidationErrors' error, though it wont tell me what the validation issue actually is.
on Inserting I got the same error but was able to fix it using the following
var underlyingContext = this.context as DbContext;
if (underlyingContext != null)
{
foreach (var table in batchDefinition.Tables)
{
// Need to mark the table entity as unchanged or
// else EF will treat it as a new table
underlyingContext.Entry(table).State = EntityState.Unchanged;
}
}
so I tried using that in this update function
var underlyingContext = this.context as DbContext;
if (underlyingContext != null)
{
foreach (var table in foundDefinition.Tables)
{
// Need to mark the table entity as unchanged or
//else EF will treat it as a new table
underlyingContext.Entry(table).State = EntityState.Unchanged;
}
}
foundDefinition.Tables = batchToUpdate.Tables;
and I get the following error instead:
AcceptChanges cannot continue because the object's key values conflict
with another object in the ObjectStateManager. Make sure that the key
values are unique before calling AcceptChanges.
Any thoughts one what I am missing here?

Change end of your update method like this:
foreach (var t in foundDefinition.Tables.ToList())
Context.Tables.Remove(t);
foundDefinition.Tables = batchToUpdate.Tables;
this.context.SaveChanges();
And about your last error, it is said that there are some duplicates in your context. So, EF can't save the context changes into the db (because there are duplicates in the context!)
In fact, I don't know the last error is from add or delete - you didn't mention clearly. So, I don't know the last two code samples are from your add method, or your update method...
However for update, the trick I mentioned here, must solve your problem for update...

SqlBulkCopy Multiple Tables Insert under single Transaction OR Bulk Insert Operation between Entity Framework and Classic Ado.net

I have two tables which need to be inserted when my application run.
Let's say that I have tables as followed
tbl_FirstTable and tbl_SecondTable
My problem is data volume.
I need to insert over 10,000 rows to tbl_FirstTable and over 500,000 rows to tbl_SecondTable.
So fristly, I use entity framework as follow.
public bool Save_tbl_FirstTable_Vs_tbl_SecondTable(List<tbl_FirstTable> List_tbl_FirstTable, List<tbl_SecondTable> List_tbl_SecondTable)
{
bool IsSuccessSave = false;
try
{
using (DummyDBClass_ObjectContext _DummyDBClass_ObjectContext = new DummyDBClass_ObjectContext())
{
foreach (tbl_FirstTable _tbl_FirstTable in List_tbl_FirstTable)
{
_DummyDBClass_ObjectContext.tbl_FirstTable.InsertOnSubmit(_tbl_FirstTable);
}
foreach (tbl_SecondTable _tbl_SecondTable in List_tbl_SecondTable)
{
_DummyDBClass_ObjectContext.tbl_SecondTable.InsertOnSubmit(_tbl_SecondTable);
}
_DummyDBClass_ObjectContext.SubmitChanges();
IsSuccessSave = true;
}
}
catch (Exception ex)
{
Log4NetWrapper.WriteError(string.Format("{0} : {1} : Exception={2}",
this.GetType().FullName,
(new StackTrace(new StackFrame(0))).GetFrame(0).GetMethod().Name.ToString(),
ex.Message.ToString()));
if (ex.InnerException != null)
{
Log4NetWrapper.WriteError(string.Format("{0} : {1} : InnerException Exception={2}",
this.GetType().FullName,
(new StackTrace(new StackFrame(0))).GetFrame(0).GetMethod().Name.ToString(),
ex.InnerException.Message.ToString()));
}
}
return IsSuccessSave;
}
That is the place I face error Time out exception.
I think that exception will be solved If I use below code.
DummyDBClass_ObjectContext.CommandTimeout = 1800; // 30 minutes
So I used it. It solved but I face another error OutOfMemory Exception.
So I searched the solutions, fortunately, I found below articles.
Problem with Bulk insert using Entity Framework
Using Transactions with SqlBulkCopy
Performing a Bulk Copy Operation in a Transaction
According to that articles, I change my code from Entity Framework to Classic ADO.net code.
public bool Save_tbl_FirstTable_Vs_tbl_SecondTable(DataTable DT_tbl_FirstTable, DataTable DT_tbl_SecondTable)
{
bool IsSuccessSave = false;
SqlTransaction transaction = null;
try
{
using (DummyDBClass_ObjectContext _DummyDBClass_ObjectContext = new DummyDBClass_ObjectContext())
{
var connectionString = ((EntityConnection)_DummyDBClass_ObjectContext.Connection).StoreConnection.ConnectionString;
using (SqlConnection connection = new SqlConnection(connectionString))
{
connection.Open();
using (transaction = connection.BeginTransaction())
{
using (SqlBulkCopy bulkCopy_tbl_FirstTable = new SqlBulkCopy(connection, SqlBulkCopyOptions.KeepIdentity, transaction))
{
bulkCopy_tbl_FirstTable.BatchSize = 5000;
bulkCopy_tbl_FirstTable.DestinationTableName = "dbo.tbl_FirstTable";
bulkCopy_tbl_FirstTable.ColumnMappings.Add("ID", "ID");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("UploadFileID", "UploadFileID");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("Active", "Active");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("CreatedUserID", "CreatedUserID");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("CreatedDate", "CreatedDate");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("UpdatedUserID", "UpdatedUserID");
bulkCopy_tbl_FirstTable.ColumnMappings.Add("UpdatedDate", "UpdatedDate");
bulkCopy_tbl_FirstTable.WriteToServer(DT_tbl_FirstTable);
}
using (SqlBulkCopy bulkCopy_tbl_SecondTable = new SqlBulkCopy(connection, SqlBulkCopyOptions.KeepIdentity, transaction))
{
bulkCopy_tbl_SecondTable.BatchSize = 5000;
bulkCopy_tbl_SecondTable.DestinationTableName = "dbo.tbl_SecondTable";
bulkCopy_tbl_SecondTable.ColumnMappings.Add("ID", "ID");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("UploadFileDetailID", "UploadFileDetailID");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("CompaignFieldMasterID", "CompaignFieldMasterID");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("Value", "Value");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("Active", "Active");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("CreatedUserID", "CreatedUserID");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("CreatedDate", "CreatedDate");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("UpdatedUserID", "UpdatedUserID");
bulkCopy_tbl_SecondTable.ColumnMappings.Add("UpdatedDate", "UpdatedDate");
bulkCopy_tbl_SecondTable.WriteToServer(DT_tbl_SecondTable);
}
transaction.Commit();
IsSuccessSave = true;
}
connection.Close();
}
}
}
catch (Exception ex)
{
if (transaction != null)
transaction.Rollback();
Log4NetWrapper.WriteError(string.Format("{0} : {1} : Exception={2}",
this.GetType().FullName,
(new StackTrace(new StackFrame(0))).GetFrame(0).GetMethod().Name.ToString(),
ex.Message.ToString()));
if (ex.InnerException != null)
{
Log4NetWrapper.WriteError(string.Format("{0} : {1} : InnerException Exception={2}",
this.GetType().FullName,
(new StackTrace(new StackFrame(0))).GetFrame(0).GetMethod().Name.ToString(),
ex.InnerException.Message.ToString()));
}
}
return IsSuccessSave;
}
Finally, It perform insert process in less than 15 seconds for over 500,000 rows.
There is two reasons why I post this scenario.
I would like to share what I found out.
As I am not perfect, I still need to get more suggestion from you.
So, every better solution will be appreciated.

1) Use EF6.x, which has much better performance than EF5.x
Here are more suggestions (from Bulk insert with EF)
2) Keep the active Context Graph small by using a new context for each Unit of Work
3) Turn off AutoDetechChangesEnabled - context.Configuration.AutoDetectChangesEnabled = false;
4) Batching, in your loop, Call SaveChanges periodically

I use payed Entity Framework extension from ZZZ Projects which is developer friendly because of fluent API (extenssion methods, functional approach). This is not an andvertisment, I use it in business projects for several years and it is great. If You want to use something for free and You have Oracle database the Oracle Managed Data Access Oracle.ManagedDataAccess.Core has implementation of bulk operations.

Bulk Operations are not really what ORMs are meant for. For bulk insert operations, I send xml to the stored procedure, and I shred it and bulk insert/update or merge from there.
So even when I use an ORM, I create a Domain Library that is not EF (or NHibernate) dependent.so I have a "safety valve" to bypass the ORM in certain situations.
You should look at using the System.Data.SqlClient.SqlBulkCopy for this. Here's the documentation- http://msdn.microsoft.com/en-us/library/system.data.sqlclient.sqlbulkcopy.aspx, and of course there are plenty of tutorials online.
In case we want EF to bulk insert records, would suggest below points to improve performance
Call SaveChanges() after for example 100 records and dispose the context and create a new one.
Disable change detection
Example:
using (TransactionScope scope = new TransactionScope())
{
MyDbContext context = null;
try
{
context = new MyDbContext();
context.Configuration.AutoDetectChangesEnabled = false;
int count = 0;
foreach (var entityToInsert in someCollectionOfEntitiesToInsert)
{
++count;
context = AddToContext(context, entityToInsert, count, 100, true);
}
context.SaveChanges();
}
finally
{
if (context != null)
context.Dispose();
}
scope.Complete();
}
private MyDbContext AddToContext(MyDbContext context,
Entity entity, int count, int commitCount, bool recreateContext)
{
context.Set<Entity>().Add(entity);
if (count % commitCount == 0)
{
context.SaveChanges();
if (recreateContext)
{
context.Dispose();
context = new MyDbContext();
context.Configuration.AutoDetectChangesEnabled = false;
}
}
return context;
}
For the performance it is important to call SaveChanges() after "many" records ("many" around 100 or 1000). It also improves the performance to dispose the context after SaveChanges and create a new one.
This clears the context from all entites, SaveChanges doesn't do that, the entities are still attached to the context in state Unchanged. It is the growing size of attached entities in the context what slows down the insertion step by step.
So, it is helpful to clear it after some time.
AutoDetectChangesEnabled = false; on the DbContext.
It also has a big additional performance effect: Why is inserting entities in EF 4.1 so slow compared to ObjectContext?.
below combination increase speed well enough in EF.
context.Configuration.AutoDetectChangesEnabled = false;
context.Configuration.ValidateOnSaveEnabled = false;