I'm new to the world of FakeXrmEasy and trying to implement some unit tests in large existing code base written by another team :)
I have an entity set in OnPremise DynamicsCRM app where the entity has the following properties:
[Microsoft.Xrm.Sdk.AttributeLogicalNameAttribute("statuscode")]
public Microsoft.Xrm.Sdk.OptionSetValue statuscode
{
get
{
return this.GetAttributeValue<Microsoft.Xrm.Sdk.OptionSetValue>("statuscode");
}
set
{
this.OnPropertyChanging("statuscode");
this.SetAttributeValue("statuscode", value);
this.OnPropertyChanged("statuscode");
}
}
/// <summary>
/// Invoice
/// </summary>
[Microsoft.Xrm.Sdk.AttributeLogicalNameAttribute("invoiceid")]
public Microsoft.Xrm.Sdk.EntityReference InvoiceId
{
get
{
return this.GetAttributeValue<Microsoft.Xrm.Sdk.EntityReference>("invoiceid");
}
set
{
this.OnPropertyChanging("InvoiceId");
this.SetAttributeValue("invoiceid", value);
this.OnPropertyChanged("InvoiceId");
}
}
So my InvoiceId is an EntityReference & my statuscode property is an OptionSetValue type. I have a query to return me entities that match InvoiceId && statuscode != X but record is being returned where invoice id matches but also if the statuscode.Value == X so only the first part of the where is applied or the 2nd part fails but result still added.
My query is:
var result = (from qa in ctx.allocationSet
where qa.InvoiceId.Id == invoiceId
&& qa.statuscode.Value != 2
select qa);
So in essence if I populate 2 records in this set, 1 with InvoiceId abc-123 and statuscode = 1, then another with InvoiceId XYZ-987 with statuscode = 2, then search for invoiceId XYZ-987 my query should return zero records but this returns the 2nd record everytime even though the statuscode.Value ==2?
The query in FakeXrmEasy will return results based on the current state of the in-memory database.
If you make a change to an entity record without actually persisting it into the in-memory database (that is, without actually calling methods like service.Create, service.Update, service.Delete, and so on), then these changes won't be persisted into the database, and so, the changes won't be reflected when retrieving data from it.
This behaviour actually mimics CDS / the Organization Service. If you set an entity attribute in code, without actually saving it back to CDS / CRM / OrgService, then when you retrieve it, it won't be there because it wasn't actually updated in the real database.
So same concept with FakeXrmEasy really.
My issue appears to be related to how the data is initialised/set.
If I set up the entity with the value before calling the XrmFakedContext then the query behaves as expected but if after initialisation I update the statuscode manually as below, the weirdness happens.
var allocation = ctx.allocationSet.First(x => x.InvoiceId.Id == _testInvoiceId);
allocation.Attributes["statuscode"] = new OptionSetValue((int)allocation.statuscodeValues.Active);
Big thanks to Jordi at dynamicsvalue for help.
I am currently getting this error:
System.Data.SqlClient.SqlException: New transaction is not allowed because there are other threads running in the session.
while running this code:
public class ProductManager : IProductManager
{
#region Declare Models
private RivWorks.Model.Negotiation.RIV_Entities _dbRiv = RivWorks.Model.Stores.RivEntities(AppSettings.RivWorkEntities_connString);
private RivWorks.Model.NegotiationAutos.RivFeedsEntities _dbFeed = RivWorks.Model.Stores.FeedEntities(AppSettings.FeedAutosEntities_connString);
#endregion
public IProduct GetProductById(Guid productId)
{
// Do a quick sync of the feeds...
SyncFeeds();
...
// get a product...
...
return product;
}
private void SyncFeeds()
{
bool found = false;
string feedSource = "AUTO";
switch (feedSource) // companyFeedDetail.FeedSourceTable.ToUpper())
{
case "AUTO":
var clientList = from a in _dbFeed.Client.Include("Auto") select a;
foreach (RivWorks.Model.NegotiationAutos.Client client in clientList)
{
var companyFeedDetailList = from a in _dbRiv.AutoNegotiationDetails where a.ClientID == client.ClientID select a;
foreach (RivWorks.Model.Negotiation.AutoNegotiationDetails companyFeedDetail in companyFeedDetailList)
{
if (companyFeedDetail.FeedSourceTable.ToUpper() == "AUTO")
{
var company = (from a in _dbRiv.Company.Include("Product") where a.CompanyId == companyFeedDetail.CompanyId select a).First();
foreach (RivWorks.Model.NegotiationAutos.Auto sourceProduct in client.Auto)
{
foreach (RivWorks.Model.Negotiation.Product targetProduct in company.Product)
{
if (targetProduct.alternateProductID == sourceProduct.AutoID)
{
found = true;
break;
}
}
if (!found)
{
var newProduct = new RivWorks.Model.Negotiation.Product();
newProduct.alternateProductID = sourceProduct.AutoID;
newProduct.isFromFeed = true;
newProduct.isDeleted = false;
newProduct.SKU = sourceProduct.StockNumber;
company.Product.Add(newProduct);
}
}
_dbRiv.SaveChanges(); // ### THIS BREAKS ### //
}
}
}
break;
}
}
}
Model #1 - This model sits in a database on our Dev Server.
Model #1 http://content.screencast.com/users/Keith.Barrows/folders/Jing/media/bdb2b000-6e60-4af0-a7a1-2bb6b05d8bc1/Model1.png
Model #2 - This model sits in a database on our Prod Server and is updated each day by automatic feeds. alt text http://content.screencast.com/users/Keith.Barrows/folders/Jing/media/4260259f-bce6-43d5-9d2a-017bd9a980d4/Model2.png
Note - The red circled items in Model #1 are the fields I use to "map" to Model #2. Please ignore the red circles in Model #2: that is from another question I had which is now answered.
Note: I still need to put in an isDeleted check so I can soft delete it from DB1 if it has gone out of our client's inventory.
All I want to do, with this particular code, is connect a company in DB1 with a client in DB2, get their product list from DB2 and INSERT it in DB1 if it is not already there. First time through should be a full pull of inventory. Each time it is run there after nothing should happen unless new inventory came in on the feed over night.
So the big question - how to I solve the transaction error I am getting? Do I need to drop and recreate my context each time through the loops (does not make sense to me)?
After much pulling out of hair I discovered that the foreach loops were the culprits. What needs to happen is to call EF but return it into an IList<T> of that target type then loop on the IList<T>.
Example:
IList<Client> clientList = from a in _dbFeed.Client.Include("Auto") select a;
foreach (RivWorks.Model.NegotiationAutos.Client client in clientList)
{
var companyFeedDetailList = from a in _dbRiv.AutoNegotiationDetails where a.ClientID == client.ClientID select a;
// ...
}
As you've already identified, you cannot save from within a foreach that is still drawing from the database via an active reader.
Calling ToList() or ToArray() is fine for small data sets, but when you have thousands of rows, you will be consuming a large amount of memory.
It's better to load the rows in chunks.
public static class EntityFrameworkUtil
{
public static IEnumerable<T> QueryInChunksOf<T>(this IQueryable<T> queryable, int chunkSize)
{
return queryable.QueryChunksOfSize(chunkSize).SelectMany(chunk => chunk);
}
public static IEnumerable<T[]> QueryChunksOfSize<T>(this IQueryable<T> queryable, int chunkSize)
{
int chunkNumber = 0;
while (true)
{
var query = (chunkNumber == 0)
? queryable
: queryable.Skip(chunkNumber * chunkSize);
var chunk = query.Take(chunkSize).ToArray();
if (chunk.Length == 0)
yield break;
yield return chunk;
chunkNumber++;
}
}
}
Given the above extension methods, you can write your query like this:
foreach (var client in clientList.OrderBy(c => c.Id).QueryInChunksOf(100))
{
// do stuff
context.SaveChanges();
}
The queryable object you call this method on must be ordered. This is because Entity Framework only supports IQueryable<T>.Skip(int) on ordered queries, which makes sense when you consider that multiple queries for different ranges require the ordering to be stable. If the ordering isn't important to you, just order by primary key as that's likely to have a clustered index.
This version will query the database in batches of 100. Note that SaveChanges() is called for each entity.
If you want to improve your throughput dramatically, you should call SaveChanges() less frequently. Use code like this instead:
foreach (var chunk in clientList.OrderBy(c => c.Id).QueryChunksOfSize(100))
{
foreach (var client in chunk)
{
// do stuff
}
context.SaveChanges();
}
This results in 100 times fewer database update calls. Of course each of those calls takes longer to complete, but you still come out way ahead in the end. Your mileage may vary, but this was worlds faster for me.
And it gets around the exception you were seeing.
EDIT I revisited this question after running SQL Profiler and updated a few things to improve performance. For anyone who is interested, here is some sample SQL that shows what is created by the DB.
The first loop doesn't need to skip anything, so is simpler.
SELECT TOP (100) -- the chunk size
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name],
FROM [dbo].[Clients] AS [Extent1]
ORDER BY [Extent1].[Id] ASC
Subsequent calls need to skip previous chunks of results, so introduces usage of row_number:
SELECT TOP (100) -- the chunk size
[Extent1].[Id] AS [Id],
[Extent1].[Name] AS [Name],
FROM (
SELECT [Extent1].[Id] AS [Id], [Extent1].[Name] AS [Name], row_number()
OVER (ORDER BY [Extent1].[Id] ASC) AS [row_number]
FROM [dbo].[Clients] AS [Extent1]
) AS [Extent1]
WHERE [Extent1].[row_number] > 100 -- the number of rows to skip
ORDER BY [Extent1].[Id] ASC
We have now posted an official response to the bug opened on Connect. The workarounds we recommend are as follows:
This error is due to Entity Framework creating an implicit transaction during the SaveChanges() call. The best way to work around the error is to use a different pattern (i.e., not saving while in the midst of reading) or by explicitly declaring a transaction. Here are three possible solutions:
// 1: Save after iteration (recommended approach in most cases)
using (var context = new MyContext())
{
foreach (var person in context.People)
{
// Change to person
}
context.SaveChanges();
}
// 2: Declare an explicit transaction
using (var transaction = new TransactionScope())
{
using (var context = new MyContext())
{
foreach (var person in context.People)
{
// Change to person
context.SaveChanges();
}
}
transaction.Complete();
}
// 3: Read rows ahead (Dangerous!)
using (var context = new MyContext())
{
var people = context.People.ToList(); // Note that this forces the database
// to evaluate the query immediately
// and could be very bad for large tables.
foreach (var person in people)
{
// Change to person
context.SaveChanges();
}
}
Indeed you cannot save changes inside a foreach loop in C# using Entity Framework.
context.SaveChanges() method acts like a commit on a regular database system (RDMS).
Just make all changes (which Entity Framework will cache) and then save all of them at once calling SaveChanges() after the loop (outside of it), like a database commit command.
This works if you can save all changes at once.
Just put context.SaveChanges() after end of your foreach(loop).
Making your queryable lists to .ToList() and it should work fine.
FYI: from a book and some lines adjusted because it's still valid:
Invoking SaveChanges() method begins a transaction which automatically rolls back all changes persisted to the database if an exception occurs before iteration completes; otherwise the transaction commits. You might be tempted to apply the method after each entity update or deletion rather than after iteration completes, especially when you're updating or deleting massive numbers of entities.
If you try to invoke SaveChanges() before all data has been processed, you incur a "New transaction is not allowed because there are other threads running in the session" exception. The exception occurs because SQL Server doesn't permit starting a new transaction on a connection that has a SqlDataReader open, even with Multiple Active Record Sets (MARS) enabled by the connection string (EF's default connection string enables MARS)
Sometimes its better to understand why things are happening ;-)
Always Use your selection as List
Eg:
var tempGroupOfFiles = Entities.Submited_Files.Where(r => r.FileStatusID == 10 && r.EventID == EventId).ToList();
Then Loop through the Collection while save changes
foreach (var item in tempGroupOfFiles)
{
var itemToUpdate = item;
if (itemToUpdate != null)
{
itemToUpdate.FileStatusID = 8;
itemToUpdate.LastModifiedDate = DateTime.Now;
}
Entities.SaveChanges();
}
I was getting this same issue but in a different situation. I had a list of items in a list box. The user can click an item and select delete but I am using a stored proc to delete the item because there is a lot of logic involved in deleting the item. When I call the stored proc the delete works fine but any future call to SaveChanges will cause the error. My solution was to call the stored proc outside of EF and this worked fine. For some reason when I call the stored proc using the EF way of doing things it leaves something open.
We started seeing this error "New transaction is not allowed because there are other threads running in the session" after migrating from EF5 to EF6.
Google brought us here but we are not calling SaveChanges() inside the loop. The errors were raised when executing a stored procedure using the ObjectContext.ExecuteFunction inside a foreach loop reading from the DB.
Any call to ObjectContext.ExecuteFunction wraps the function in a transaction. Beginning a transaction while there is already an open reader causes the error.
It is possible to disable wrapping the SP in a transaction by setting the following option.
_context.Configuration.EnsureTransactionsForFunctionsAndCommands = false;
The EnsureTransactionsForFunctionsAndCommands option allows the SP to run without creating its own transaction and the error is no longer raised.
DbContextConfiguration.EnsureTransactionsForFunctionsAndCommands Property
Here are another 2 options that allow you to invoke SaveChanges() in a for each loop.
The first option is use one DBContext to generate your list objects to iterate through, and then create a 2nd DBContext to call SaveChanges() on. Here is an example:
//Get your IQueryable list of objects from your main DBContext(db)
IQueryable<Object> objects = db.Object.Where(whatever where clause you desire);
//Create a new DBContext outside of the foreach loop
using (DBContext dbMod = new DBContext())
{
//Loop through the IQueryable
foreach (Object object in objects)
{
//Get the same object you are operating on in the foreach loop from the new DBContext(dbMod) using the objects id
Object objectMod = dbMod.Object.Find(object.id);
//Make whatever changes you need on objectMod
objectMod.RightNow = DateTime.Now;
//Invoke SaveChanges() on the dbMod context
dbMod.SaveChanges()
}
}
The 2nd option is to get a list of database objects from the DBContext, but to select only the id's. And then iterate through the list of id's (presumably an int) and get the object corresponding to each int, and invoke SaveChanges() that way. The idea behind this method is grabbing a large list of integers, is a lot more efficient then getting a large list of db objects and calling .ToList() on the entire object. Here is an example of this method:
//Get the list of objects you want from your DBContext, and select just the Id's and create a list
List<int> Ids = db.Object.Where(enter where clause here)Select(m => m.Id).ToList();
var objects = Ids.Select(id => db.Objects.Find(id));
foreach (var object in objects)
{
object.RightNow = DateTime.Now;
db.SaveChanges()
}
If you get this error due to foreach and you really need to save one entity first inside loop and use generated identity further in loop, as was in my case, the easiest solution is to use another DBContext to insert entity which will return Id and use this Id in outer context
For example
using (var context = new DatabaseContext())
{
...
using (var context1 = new DatabaseContext())
{
...
context1.SaveChanges();
}
//get id of inserted object from context1 and use is.
context.SaveChanges();
}
I was also facing same issue.
Here is the cause and solution.
http://blogs.msdn.com/b/cbiyikoglu/archive/2006/11/21/mars-transactions-and-sql-error-3997-3988-or-3983.aspx
Make sure before firing data manipulation commands like inserts, updates, you have closed all previous active SQL readers.
Most common error is functions that read data from db and return values.
For e.g functions like isRecordExist.
In this case we immediately return from the function if we found the record and forget to close the reader.
So in the project were I had this exact same issue the problem wasn't in the foreach or the .toList() it was actually in the AutoFac configuration we used.
This created some weird situations were the above error was thrown but also a bunch of other equivalent errors were thrown.
This was our fix:
Changed this:
container.RegisterType<DataContext>().As<DbContext>().InstancePerLifetimeScope();
container.RegisterType<DbFactory>().As<IDbFactory>().SingleInstance();
container.RegisterType<UnitOfWork>().As<IUnitOfWork>().InstancePerRequest();
To:
container.RegisterType<DataContext>().As<DbContext>().As<DbContext>();
container.RegisterType<DbFactory>().As<IDbFactory>().As<IDbFactory>().InstancePerLifetimeScope();
container.RegisterType<UnitOfWork>().As<IUnitOfWork>().As<IUnitOfWork>();//.InstancePerRequest();
I know it is an old question but i faced this error today.
and i found that, this error can be thrown when a database table trigger gets an error.
for your information, you can check your tables triggers too when you get this error.
I needed to read a huge ResultSet and update some records in the table.
I tried to use chunks as suggested in Drew Noakes's answer.
Unfortunately after 50000 records I've got OutofMemoryException.
The answer Entity framework large data set, out of memory exception explains, that
EF creates second copy of data which uses for change detection (so
that it can persist changes to the database). EF holds this second set
for the lifetime of the context and its this set thats running you out
of memory.
The recommendation is to re-create your context for each batch.
So I've retrieved Minimal and Maximum values of the primary key- the tables have primary keys as auto incremental integers.Then I retrieved from the database chunks of records by opening context for each chunk. After processing the chunk context closes and releases the memory. It insures that memory usage is not growing.
Below is a snippet from my code:
public void ProcessContextByChunks ()
{
var tableName = "MyTable";
var startTime = DateTime.Now;
int i = 0;
var minMaxIds = GetMinMaxIds();
for (int fromKeyID= minMaxIds.From; fromKeyID <= minMaxIds.To; fromKeyID = fromKeyID+_chunkSize)
{
try
{
using (var context = InitContext())
{
var chunk = GetMyTableQuery(context).Where(r => (r.KeyID >= fromKeyID) && (r.KeyID < fromKeyID+ _chunkSize));
try
{
foreach (var row in chunk)
{
foundCount = UpdateRowIfNeeded(++i, row);
}
context.SaveChanges();
}
catch (Exception exc)
{
LogChunkException(i, exc);
}
}
}
catch (Exception exc)
{
LogChunkException(i, exc);
}
}
LogSummaryLine(tableName, i, foundCount, startTime);
}
private FromToRange<int> GetminMaxIds()
{
var minMaxIds = new FromToRange<int>();
using (var context = InitContext())
{
var allRows = GetMyTableQuery(context);
minMaxIds.From = allRows.Min(n => (int?)n.KeyID ?? 0);
minMaxIds.To = allRows.Max(n => (int?)n.KeyID ?? 0);
}
return minMaxIds;
}
private IQueryable<MyTable> GetMyTableQuery(MyEFContext context)
{
return context.MyTable;
}
private MyEFContext InitContext()
{
var context = new MyEFContext();
context.Database.Connection.ConnectionString = _connectionString;
//context.Database.Log = SqlLog;
return context;
}
FromToRange is a simple structure with From and To properties.
Recently I faced the same issue in my project so posting my experience and it might help some on the same boat as i was. The issue was due to i am looping through the results of EF select query (results are not retrieved into memory).
var products = (from e in _context.Products
where e.StatusId == 1
select new { e.Name, e.Type });
foreach (var product in products)
{
//doing some insert EF Queries
//some EF select quries
await _context.SaveChangesAsync(stoppingToken); // This code breaks.
}
I have updated my Products select query to bring the results into LIST rather than IQueryable (This seems to be opening the reader throughout for each loop and hence save was failing).
var products = (from e in _context.Products
where e.StatusId == 1
select new { e.Name, e.Type })**.ToList()**; //see highlighted
The code below works for me:
private pricecheckEntities _context = new pricecheckEntities();
...
private void resetpcheckedtoFalse()
{
try
{
foreach (var product in _context.products)
{
product.pchecked = false;
_context.products.Attach(product);
_context.Entry(product).State = EntityState.Modified;
}
_context.SaveChanges();
}
catch (Exception extofException)
{
MessageBox.Show(extofException.ToString());
}
productsDataGrid.Items.Refresh();
}
In my case, the problem appeared when I called Stored Procedure via EF and then later SaveChanges throw this exception. The problem was in calling the procedure, the enumerator was not disposed. I fixed the code following way:
public bool IsUserInRole(string username, string roleName, DataContext context)
{
var result = context.aspnet_UsersInRoles_IsUserInRoleEF("/", username, roleName);
//using here solved the issue
using (var en = result.GetEnumerator())
{
if (!en.MoveNext())
throw new Exception("emty result of aspnet_UsersInRoles_IsUserInRoleEF");
int? resultData = en.Current;
return resultData == 1;//1 = success, see T-SQL for return codes
}
}
I am much late to the party but today I faced the same error and how I resolved was simple. My scenario was similar to this given code I was making DB transactions inside of nested for-each loops.
The problem is as a Single DB transaction takes a little bit time longer than for-each loop so once the earlier transaction is not complete then the new traction throws an exception, so the solution is to create a new object in the for-each loop where you are making a db transaction.
For the above mentioned scenarios the solution will be like this:
foreach (RivWorks.Model.Negotiation.AutoNegotiationDetails companyFeedDetail in companyFeedDetailList)
{
private RivWorks.Model.Negotiation.RIV_Entities _dbRiv = RivWorks.Model.Stores.RivEntities(AppSettings.RivWorkEntities_connString);
if (companyFeedDetail.FeedSourceTable.ToUpper() == "AUTO")
{
var company = (from a in _dbRiv.Company.Include("Product") where a.CompanyId == companyFeedDetail.CompanyId select a).First();
foreach (RivWorks.Model.NegotiationAutos.Auto sourceProduct in client.Auto)
{
foreach (RivWorks.Model.Negotiation.Product targetProduct in company.Product)
{
if (targetProduct.alternateProductID == sourceProduct.AutoID)
{
found = true;
break;
}
}
if (!found)
{
var newProduct = new RivWorks.Model.Negotiation.Product();
newProduct.alternateProductID = sourceProduct.AutoID;
newProduct.isFromFeed = true;
newProduct.isDeleted = false;
newProduct.SKU = sourceProduct.StockNumber;
company.Product.Add(newProduct);
}
}
_dbRiv.SaveChanges(); // ### THIS BREAKS ### //
}
}
I am a little bit late, but I had this error too. I solved the problem by checking what where the values that where updating.
I found out that my query was wrong and that there where over 250+ edits pending. So I corrected my query, and now it works correct.
So in my situation: Check the query for errors, by debugging over the result that the query returns. After that correct the query.
Hope this helps resolving future problems.
My situation was similar others above. I had an IQueryable which I was doing a foreach on. This in turn called a method with SaveChanges(). Booom exception here as there was already a transaction open from the query above.
// Example:
var myList = _context.Table.Where(x => x.time == null);
foreach(var i in myList)
{
MyFunction(i); // <<-- Has _context.SaveChanges() which throws exception
}
Adding ToList() to the end of the query was the solution in my case.
// Fix
var myList = _context.Table.Where(x => x.time == null).ToList();
Most of answers related with loops. But my problem was different. While i was trying to use multiple dbcontext.Savechanges() command in same scope, i got the error many times.
In my case for ef core 3.1 using
dbcontext.Database.BeginTransaction()
and
dbcontext.Database.CommitTransaction();
has fixed the problem. Here is my entire Code :
public IActionResult ApplyForCourse()
{
var master = _userService.GetMasterFromCurrentUser();
var trainee = new Trainee
{
CourseId = courseId,
JobStatus = model.JobStatus,
Gender = model.Gender,
Name = model.Name,
Surname = model.Surname,
Telephone = model.Telephone,
Email = model.Email,
BirthDate = model.BirthDate,
Description = model.Description,
EducationStatus = EducationStatus.AppliedForEducation,
TraineeType = TraineeType.SiteFirst
};
dbcontext.Trainees.Add(trainee);
dbcontext.SaveChanges();
dbcontext.Database.BeginTransaction();
var user = userManager.GetUserAsync(User).Result;
master.TraineeId = trainee.Id;
master.DateOfBirth = model.BirthDate;
master.EducationStatus = trainee.EducationStatus;
user.Gender = model.Gender;
user.Email = model.Email;
dbcontext.Database.CommitTransaction();
dbcontext.SaveChanges();
return RedirectToAction("Index", "Home");
}
}
I have a very strange problem - sometimes my database fails to populate with Plans and Buckets, then throws the exception shown at the end when trying to save Tasks to the db. Other times the code works perfectly. I would appreciate any insight into why this could be. Could it be a timing issue with the delete commands?
EntitiesModelContainer db = new EntitiesModelContainer();
List<Plan> ignoredPlans = db.Plans.Where(p => p.Ignore).ToList();
// Delete old data completely
// foreign keys will cascade delete some tables such as buckets and tasks
db.Database.ExecuteSqlCommand("DELETE FROM Plans");
db.Database.ExecuteSqlCommand("DELETE FROM Assignees");
PlansResponse plans = GraphAPI.GetPlans();
foreach (PlanResponse plan in plans.Plans)
{
Plan planRecord = new Plan()
{
Id = plan.ID,
Title = plan.Title,
Ignore = ignoredPlans.Find(p => p.Id == plan.ID) != null
};
db.Plans.Add(planRecord);
bool changes = db.ChangeTracker.HasChanges();
int result = db.SaveChanges();
if (!planRecord.Ignore)
{
BucketsResponse buckets = GraphAPI.GetBuckets(plan);
foreach (BucketResponse bucket in buckets.Buckets)
{
Bucket bucketRecord = new Bucket()
{
Id = bucket.ID,
Name = bucket.Name,
PlanId = bucket.PlanID
};
db.Buckets.Add(bucketRecord);
db.SaveChanges();
}
TasksResponse tasks = GraphAPI.GetTasks(plan);
foreach (TaskResponse task in tasks.Tasks)
{
Task taskRecord = new Task()
{
Id = task.ID,
Title = task.Title,
Progress = task.PercentComplete,
Description = task.HasDescription ? GraphAPI.GetTaskDetails(task).Description : null,
CreatedDateTime = task.CreatedDateTime,
DueDateTime = task.DueDateTime,
CompletedDateTime = task.CompletedDateTime,
PlanId = task.PlanID,
BucketId = task.BucketID
};
db.Tasks.Add(taskRecord);
db.SaveChanges();
The last line is where the error occurs.
SqlException: The INSERT statement conflicted with the FOREIGN KEY constraint "FK_PlanTask". The conflict occurred in database "Dashboard-dev", table "dbo.Plans", column 'Id'. The statement has been terminated.
The strange thing is, it doesn't always throw! Any help would be appreciated.
Update: You're right - it appears the code is running twice, concurrently. Why? I didn't (intentionally) mean to do this...
public class DBController : Controller
{
public ActionResult Index()
{
DBAccess.UpdateData();
return View();
}
}
The snippet posted above is the start of this method UpdateData().
Since it's complaining about the foreign key PlanId (I'm guessing), I'd say GetTasks somehow returns an incorrect PlanId.
To get to the bottom of it I'd set up a profiler session and examine the SQL statements when there's an error. Or just examine the objects in the debugger when the exception happens, I guess. The values of the properties should give a clue as to what's going on.
Edit: I just noticed your first line says 'sometimes it fails to populate with plans and tasks', missed that. I don't understand how it would continue if it couldn't save a plan, but a SQL profiler session might be able to answer that.
Edit after the fact: of course the simplest answer could be concurrency, especially if this is a web application, two requests could be coming in at the same time and overlapping.
Can tasks have a null PlanID (why it might work sometimes)? The delete at the top looks suspicious, shouldn't you be setting the PlanID to the newly created planRecord? Either way you are setting it to a Plan that no longer exists so a cascade might not be working somewhere ( if for example it was supposed to nullify dead plans as foreign keys to Task and Bucket).
I have a method that receive the IDs of some rows to delete. I am using a code like this:
public bool delete(IEnumerable<long> paramIeId)
{
using(myContext)
{
foreach(long iterator in paramIeId)
{
nyDbContext.Remove(new MyType(){ID = iterator});
}
}
}
It works fine because delete the rows when exists. But If there area 1 or more rows that doesn't exist then I get an exception and no one rows are delete, although some of them exists.
If I do this query in T-SQL I don't have problems, the database delete the exisiting rows and igonre the no exisiting rows because at the end I want to delete them so if another process deleted them for me, no problem.
I could handle the optimistic concurrency exception refreshing the dbContextfrom database, but I think that it is to do extra queries that they could be avoid.
Is there any way that EF works like T-SQL? If I try to delete a row that doen't exists, ignore it and delete the rest of the rows.
Thanks.
At least for now, the exception seems unavoidable when using detached entities to perform the delete. You'll either have to use a try / catch and handle the exception or query the DB for matching id's and only delete matches1.
Sample With Exception Handling
using (myContext)
{
foreach (long iterator in paramIeId)
{
nyDbContext.Remove(new MyType() { ID = iterator });
}
try
{
nyDbContext.SaveChanges()
}
catch(DbUpdateConcurrencyException ex)
{
//if you want special handling for double delete
}
}
Sample With Query then Delete
Note that I query the entire list of types before the loop to avoid making separate queries on each type.
using (myContext)
{
var existingMyTypes = nyDbContext.MyTypes.Where(x => paramIeId.Contains(x.ID));
foreach (MyType existing in existingMyTypes)
{
nyDbContext.Remove(existing);
}
nyDbContext.SaveChanges();
}
1 NOTE: The query then delete option leaves open a possible race condition which could trigger the OptimisticConcurrencyException you're trying to - namely, if another process / thread / program deletes the rows between your own processes's read and delete. The only way to completely handle that possibility is by handling the exception in a try / catch.
You don't need to create a new object to delete it, just let EF handle everything for you:
public bool delete(IEnumerable<long> paramIeId)
{
using(var nyDbContext = new DbContext())
{
foreach(long id in paramIeId)
{
MyType myType = nyDbContext.MyTypes.FirstOrDefault(x => x.ID == id);
if (myType != null)
{
nyDbContext.MyTypes.Remove(myType);
}
}
nyDbContext.SaveChanges();
}
}
I'm trying to add a bulk of data in my DbContext (SQLite DB).
What I want is to add x amount of data, and if some of them already exist, ignore those. So for example: add 100, 2 already exist, 98 items are added.
First I did a insert of all of them and then call saveChanges(), but that reverted the insert of all of them. Therefore I changed it to saveChanges() in the for-loop but I'm experiencing the same problem.
Do I need to clear something after an exception?
public int Insert(List<Car> Cars)
{
int addedCars = 0;
foreach (Car t in Cars)
{
_db.Cars.Add(t);
try
{
_db.SaveChanges();
addedCars++;
}
catch (DbUpdateException ex)
{
Console.WriteLine("Whups duplicate entry");
}
}
return addedCars;
}
You would need to remove it from the context. You're receiving an exception, but the entity is still "added" to the context. So the next time you SaveChanges(), you'll get the same exception.
Option 1:
public int Insert(List<Car> Cars)
{
int addedCars = 0;
foreach (Car t in Cars)
{
_db.Cars.Add(t);
try
{
_db.SaveChanges();
addedCars++;
}
catch (DbUpdateException ex)
{
_db.cars.Remove(t); // Remove it from the context collection
Console.WriteLine("Whups duplicate entry");
}
}
return addedCars;
}
Option 2 (preferred):
I really suggest you not even attempt to add the entities if they already exist.
You could do this before your add logic:
Cars = Cars.Where(x => !_db.Cars.Any(y => y.ID == x.ID)).ToList();
Note that even though this technically "checks" 100 records, it is doing so in memory with a single SQL statement. This is much faster than inserting even a few records erroneously.
Can't you just test if the item already exists before adding it?
if(!_db.Cars.Any(c => c == t))
{
_db.Cars.Add(t);
}