EF4 - Changes not being captured between sessions - entity-framework

I'm trying to test detaching an entity from one context, making modifications to it, creating a new context, attaching it, and having the changes made between sessions persist. I don't seem to be able to get this working appropriately. I've tried calling DetectChanges as well as ApplyCurrentValues w/ no success. Below is what I've got so far. These aren't POCO's and I don't want to treat them as such. I just want to be able to detach an entity, make changes to it, and re-attach it. Thanks!
OCConsumer consumer;
using (var ctx1 = new CMSStagingContext())
{
consumer = (from c in ctx1.OCConsumers
select c).FirstOrDefault();
Console.WriteLine("Retrieved {0} - {1} {2}",
consumer.CustomerId, consumer.FirstName, consumer.LastName);
ctx1.Detach(consumer);
}
consumer.BirthDate = "10/22/1981";
using (var ctx2 = new CMSStagingContext())
{
ctx2.Attach(consumer);
ctx2.ApplyCurrentValues("OCConsumers", consumer);
ctx2.SaveChanges(System.Data.Objects.SaveOptions.DetectChangesBeforeSave | System.Data.Objects.SaveOptions.AcceptAllChangesAfterSave);
}

When you attach an object to a context, the context is going to presume that the object is unmodified, unless you tell it otherwise. The simplest way to do this is to attach the object to the context first, then modify it. So you could change your code to:
OCConsumer consumer;
using (var ctx1 = new CMSStagingContext())
{
consumer = (from c in ctx1.OCConsumers
select c).FirstOrDefault();
Console.WriteLine("Retrieved {0} - {1} {2}",
consumer.CustomerId, consumer.FirstName, consumer.LastName);
ctx1.Detach(consumer);
}
using (var ctx2 = new CMSStagingContext())
{
ctx2.Attach(consumer);
consumer.BirthDate = "10/22/1981";
ctx2.SaveChanges(System.Data.Objects.SaveOptions.DetectChangesBeforeSave | System.Data.Objects.SaveOptions.AcceptAllChangesAfterSave);
}
Another approach would be to use Context.ObjectStateManager.ChangeObjectState.

Related

How to get rid of lots of soql queries using maps

Im finding it really hard to understand maps, I have read lots of examples but they always seem not to relate to what I need to do - I've just about understood how to use oldmap.trigger in a very simple use case.
So anyways I have a trigger on a object Data_ProtectionIA , its parent is Data Agreement, and then its parent is Data request.
I need to update Data agreement and Data request when DPIA gets updated, I have the below so far which I know is a very long winded way to do it, but now I also have to add further updates for when DPIA gets updated to something else and for me to do this like I have done would mean doubling this code again when it is already unnecesarily long.
If someone could please simplify this code into maps then I think I would be able to understand maps properly, I just cant find examples of what I need to do. Many thanks in advance
(So at the moment I am getting the grandchild record and then creating a list of parent records to loop through and then getting a list of all their parent records and then looping through that. - even if you could just show me from child to parent (not even, child parent to grandparent that would be very helpful)
public static void setDRStatus(List<Data_Protection_IA__c> dpia, Map<ID,Data_Protection_IA__c> oldMap ){
List<ID> childDAID = new List<ID>();
for(Data_Protection_IA__c pDA: dpia){
if(pDA.DPIA_Status__c == 'Fully Approved' && oldMap.get(pDA.Id).DPIA_Status__c != 'Fully Approved'){
childDAID.add(pDA.DataProcessingAgreement__c);
}
}
List<Data_Agreement__c> childDA = new List<Data_Agreement__c>();
ChildDA = [Select id, Data_Sharing_Status__c from Data_Agreement__c where id in:childDAID];
List<Data_Agreement__c> listToUpdate = new List <Data_Agreement__c>();
List<ID> dAId = new List <ID>();
system.debug('ChildDA'+ childDA);
for(Data_Agreement__c cda : ChildDA){
cda.Data_Sharing_Status__c = 'DPIA Fully Approved';
listToUpdate.add(cda);
dAId.add(cda.id);
}
update listToUpdate;
List<Data_Request__c> dRList = [SELECT id, Data_Sharing_Status__c,Existing_Data_Agreement__c
FROM Data_Request__c where Existing_Data_Agreement__c in:dAId];
List<Data_Request__c> listToUpdatedr = new List <Data_Request__c>();
system.debug('DRList'+ dRList);
for(Data_Request__c dr :dRList){
dr.Data_Sharing_Status__c = 'DPIA Approved';
listToUpdatedr.add(dr);
}
update listToUpdatedr;
}
----------------------------------------
Here is an example I had previously tried
So I started following an example and got to here
Set<Id> daIds = new Set<Id> {};
for (Data_Protection_IA__c p : dpia)
{
daIds.add(p.DataProcessingAgreement__c );
}
Map<ID, Data_Agreement__c> m = new Map<ID, Data_Agreement__c>(
[select id, from Data_Agreement__c where id in : daIds]);
list<Data_Agreement__c> dAupdates = new List <Data_Agreement__c>();
list<Contact> contactupdates = new List <Contact>();
for (Data_Protection_IA__c p1 :dpia)
{
m.get(p1.Data_Agreement__c) = 'DPIA Fully Approved');
}
but at the last line I think this map is tying to get the field Data_agreement from dpia object, but there is no data agreement field on dpia object. as dpia is the child. there is only a field for dpia on the data agreement object

Entity Framework Core throw DbUpdateConcurrencyException

I am working on .net core entity framework. I have two list of class type. One for update and other for new entry, adding new records all worked fine but which is achieved by context.[Model].Add but update which is done by context.[Model].Update throw exception update i know no record been updated as it is running on local.
$exception {Microsoft.EntityFrameworkCore.DbUpdateConcurrencyException: Database operation expected to affect 1 row(s) but actually affected 0 row(s). Data may have been modified or deleted since entities were loaded.
Code
List<AnswerDataModel> surveyResponseListToCreate = new
List<AnswerDataModel>();
List<AnswerDataModel> surveyResponseListToUpdate = new
List<AnswerDataModel>();
if (surveyResponseListToUpdate.Count > 0)
{
foreach (var answerObject in surveyResponseListToUpdate)
{
Context.Answers.Update(answerObject);
if (answerObject.AnswerOptions.Count > 0)
{
foreach (var optItem in answerObject.AnswerOptions)
{
AnswerOptionDataModel answOpt = new AnswerOptionDataModel();
answOpt = optItem;
Context.AnswerOptions.Update(answOpt);
}
}
}
}
var recordsAffected = Context.SaveChanges();
if (!UsingExternalTransaction)
{
FinalizeTransaction(recordsAffected);
}
I can't resist a quote:
"I do not think [your code] means what you think it means."
Assuming that surveyResponseListToUpdate was a list of entities previously loaded and modified:
if (answerObject.AnswerOptions.Count > 0) // Unnecessary...
{
foreach (var optItem in answerObject.AnswerOptions)
{
AnswerOptionDataModel answOpt = new AnswerOptionDataModel(); // does nothing.
answOpt = optItem; // references existing answer option..
Context.AnswerOptions.Update(answOpt);
}
}
The whole block boils down to:
foreach (var optItem in answerObject.AnswerOptions)
Context.AnswerOptions.Update(optItem);
The error you are likely running into is because Update will recurse through navigation properties automatically, so when the parent (Answer) is updated, it's AnswerOptions will be updated as well. So when you go through the extra steps to try and save answer options, they've already been updated when the answer was saved. Provided the Answer was loaded by the same context that you are saving it to, you should be in the clear with:
foreach (var answerObject in surveyResponseListToUpdate)
Context.Answers.Update(answerObject);
var recordsAffected = Context.SaveChanges();
This should update the answer and it's associated answer objects. Even if options were added or removed, the change tracking should do it's job and ensure all of the associated data records are updated.
The extra if checks and such aren't necessary and just add to nesting depth making code harder to read.
However, I suspect that your real code is doing something different to the example given that my tests where I tried to reproduce your error, the code worked fine even updating the child references after updating the parent. If the above still raises issues, please update your example with the code you are running.

How to get the current tool SitePage and/or its Properties?

With the ToolManager I can get the the current placement, the context and of course, the Site through the SiteService. But I want to get the current SitePage properties the user is currently accessing.
This doubt can be extended to the current Tool properties with a
little more emphasis considering that once I have the Tool I could not
find any methods covering the its properties.
I could get the tool properties and I'm using it (it is by instance) through Properties got with sitepage.getTool(TOOLID).getConfig(). To save a property, I'm using the ToolConfiguration approach and saving the data after editing with the ToolConfiguration.save() method. Is it the correct approach?
You can do this by getting the current tool session and then working your way backward from that. Here is a method that should do it.
public SitePage findCurrentPage() {
SitePage sp = null;
ToolSession ts = SessionManager.getCurrentToolSession();
if (ts != null) {
ToolConfiguration tool = SiteService.findTool(ts.getPlacementId());
if (tool != null) {
String sitePageId = tool.getPageId();
sp = s.getPage(sitePageId);
}
}
return sp;
}
Alternatively, you could use the current tool to work your way to it but I think this method is harder.
String toolId = toolManager.getCurrentTool().getId();
String context = toolManager.getCurrentPlacement().getContext();
Site s = siteService.getSite( context );
ToolConfiguration tc = s.getTool(toolId);
String sitePageId = tc.getPageId();
SitePage sp = s.getPage(sitePageId);
NOTE: I have not tested this code to make sure it works.

EF6 Cannot Delete/Update - An object with the same key already exists in the ObjectStateManager

I am using EF 6 Code First and I need to delete an item and then also update a different item within a collection of Entities. If I try to delete one item and then modify a completely different item I get the error message "An object with the same key already exists in the ObjectStateManage" This is inaccurate because there are two objects with completely different PK IDs but when the update happens it throws the error. If I comment out the code to delete then the update works just fine with multiple items to update. Why would it complain about the "same key" when the keys are different?
foreach (var phone in phones)
{
if (!_isValidPhone(phone))
{
if(phone.PhoneId != 0)
{
var deletePhone = _db.Phones.FirstOrDefault(r => r.PhoneId == phone.PhoneId);
_db.Entry(deletePhone).State = EntityState.Deleted;
continue;
}
}
if (_isNewPhone(phone))
{
AddNewPhone(phone, _person);
}
else
{
UpdatePhoneData(phone, _person.Phones.FirstOrDefault(r => r.Order == phone.Order));
}
}
private void UpdatePhoneData(Phone phoneFrom, Phone phoneTo)
{
phoneTo.Note = phoneFrom.Note;
phoneTo.PhoneNumber = phoneFrom.PhoneNumber;
phoneTo.Order = phoneFrom.Order;
_db.Entry(phoneTo).State = EntityState.Modified;
}
If a phone is not valid and has id you try to add it to the context in two ways:
While deleting it:
_db.Entry(deletePhone).State = EntityState.Deleted;
Besides, when checking if it's new or not you either add or update it. Thats the problem.
So, what you need to do is wrap the add or update part inside an else, to add or update only if the phone has not been deleted.
This is not really a logic issue, the phone that was being updated is completely different than the phone that was being deleted. The issue is in the object statemanager. Because I was doing this in the delete
var deletePhone = _db.Phones.FirstOrDefault();
And then later I had a separate list of Phones where I try to set one of them to modified
_db.Entry(phoneTo).State = EntityState.Modified;
Well the object state manager now has each phone loaded twice basically. So if I just use the _person.Phones for both my delete and modify, then the Phones list is only loaded once and there are now duplicate keys.
_db.Entry(_person.Phones.FirstOrDefault(r => r.PhoneId == phone.PhoneId)).State = EntityState.Deleted;

Entity Framework - Caching issue

The problem I am having is as follows, due to caching issues we are putting the following before the start of every ET query:
DataBase.Refresh(System.Data.Objects.RefreshMode.ClientWins, DataBase.PublicUsers);
However, this is causing pages to take ages to load as the above command makes two calls to the database.
Does anybody know away to stop EF from caching without having to put that command before every query?
To answer your initial question. If you don't want context to cache data you must execute query without change tracking.
Database.Hubs.MergeOption = MergeOption.NoTracking;
return DataBase.Hubs
.Where(h =>
h.BusinessId == null
&& h.TypeId != (int)HubType.BusinessPlace
&& h.ParentHubId != null
);
But this will not solve your architecture issue related to static / shared context in a web app. You must change your architecture if you really want to create working application.
You can set the MergeOption to all EntitieSet after create the context. Some like this:
var objSetProps = ctx.GetType().GetProperties().Where(prop => prop.PropertyType.IsGenericType && prop.PropertyType.GetGenericTypeDefinition() == typeof(ObjectSet<>));
foreach (PropertyInfo objSetProp in objSetProps)
{
ObjectQuery objSet = (ObjectQuery)objSetProp.GetValue(ctx, BindingFlags.GetProperty, null, null, null);
objSet.MergeOption = MergeOption.PreserveChanges;
}
Read about the MergeOption here: http://msdn.microsoft.com/en-us/library/system.data.objects.mergeoption.aspx
Your will use NoTracking, I think.
But, iy you whant CLEAR the "cached" entities, detaching it.
var entidades = Ctx.ObjectStateManager.GetObjectStateEntries(EntityState.Added | EntityState.Deleted | EntityState.Modified | EntityState.Unchanged);
foreach (var objectStateEntry in entidades)
Ctx.Detach(objectStateEntry.Entity);
Where Ctx are my Context.