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Cannot Attach An Entity That Already Exists Deleteonsubmit

Marked as answer by Michael Sun [MSFT]Microsoft employee, Moderator Monday, March 22, 2010 9:28 AM Wednesday, March 17, 2010 12:05 PM Reply | Quote All replies 0 Sign in to vote current community chat Stack Overflow Meta Stack Overflow your communities Sign up or log in to customize your list. share|improve this answer answered Mar 25 '09 at 18:44 Quintin Robinson 56.9k1295120 I used to have db.MatchUpdateQueues.DeleteOnSubmit(db.MatchUpdateQueues.Fir‌stOrDefault(x => x.id == item.id)); but that threw up the same exception, so Huh? Source

It is also possible to tell LINQ to SQL to 'just update all the fields', you do this with the Attach overload that takes a boolean second parameter. It used to be the only one, and even so, it still gave me those problems when trying to re-create an element that had been previously deleted. whoops! double edit: everyone who answered was correct! http://stackoverflow.com/questions/682890/deleteonsubmit-linq-exception-cannot-add-an-entity-with-a-key-that-is-already-i

DateTime values run the risk of DLS changes and I'm not sure how this affects "timestamp" datatypes. using (aDataContext db = new aDataContext()) { var dbItem = db.MatchUpdateQueues.Single(i => i.Id == item.Id); db.MatchUpdateQueues.DeleteOnSubmit(dbItem); db.SubmitChanges(); } share|improve this answer edited Mar 25 '09 at 20:04 answered Mar 25 '09 The idea is that you have wrapper methods for CRUD (and all other data access) in the business layer so you'd write code like this: busCustomerBasic Customer = new busCustomerBasic();tt_customer cust This won't affect connections, as they are open/closed only when doing operations that need them.

Is it possible to write division equation in more rows? Entries in this series:Linq to SQL Quirks Part 1: Implicit InsertsLinq to SQL Quirks Part 2: DeleteOnSubmit and Entity not AttachedLinq to SQL Quirks Part 3 - Extension to Get Around How many instances of the outer class do you have instantiated? I searched how to disable the DataContext cache....

Entity Framework for Existing Database Update existing entity from database Advertise | Privacy | Mobile Web01 | 2.8.161101.1 | Last Updated 20 May 2015 Copyright © CodeProject, 1999-2016 All Rights Reserved. Everytime you make a SubmitChanges(); You have update your reference, because its old. read an instance from the database and compare properties), or otherwise assume that everything has changed and needs to be updated (ie. http://stackoverflow.com/questions/13684748/getting-the-error-cannot-add-an-entity-that-already-exists-while-inserting-a Browse other questions tagged c# linq or ask your own question.

second if you set the PK property you get an exception so what you do is add a new contructor via partial class ... If you store objects in session then you may want to store the instance in session as well. Safely adding insecure devices to my home network Was there no tax before 1913 in the United States? Cannot add an entity that already exists. [Answered]RSS 6 replies Last post Jul 13, 2009 02:55 AM by kashmirindotnet ‹ Previous Thread|Next Thread › Print Share Twitter Facebook Email Shortcuts Active

Tank-Fighting Alien Why was Susan treated so unkindly? have a peek at this web-site Sign in using Search within: Articles Quick Answers Messages Use my saved content filters home articles Chapters and Sections> Search Latest Articles Latest Tips/Tricks Top Articles Beginner Articles Technical Blogs Posting/Update Solved- PromoCodeForSpecificBook1 obj; foreach(var i in Model.BookDetail) { obj = new PromoCodeForSpecificBook1(); obj.BookId = i.ID; //Convert.ToInt32(Model.Id); var P = DB.BookPromoCodes.OrderByDescending(X => X.Id).FirstOrDefault().Id; obj.PromoCodeId =P; DB.PromoCodeForSpecificBook1s.InsertOnSubmit(obj); DB.SubmitChanges(); } Posted 19-May-15 Rick Strahl January 24, 2008 # re: LINQ to SQL and attaching Entities Yeah sure - but isn't that the point?Linq to Entities isn't here yet and probably won't be for

It's rather easy once you know how to do it:http://christophekeller.blogspot.com/2010/02/linq-to-sql-updating-reattached-entity.html Rick Strahl February 12, 2010 # re: LINQ to SQL and attaching Entities @Christophe, uhm not really. http://electrictricycle.net/cannot-attach/cannot-attach-the-file-as-database-entity-framework.html Better Tag Cloud Rick Strahl's Web Log Wind, waves, code and everything in between... For all those facing similar problems,here is a clear solution: You need to create the object of the 'Table' class(which object you want to update in DB), inside the loop(*for each,for The Context/Tables hold all of the information necessary to figure out what's changed and it would be a fairly trivial matter - using Reflection or simply using a full field SQL

Not the answer you're looking for? I am having the same issue? Could I work as a Professor in Europe if I only speak English? http://electrictricycle.net/cannot-attach/cannot-attach-an-entity-that-already-exists-delete.html Now although I don't think this is great it's not as terrible as it might sound given that the DataContext is not actually connected to the database - all data access

Thanks in advance. Matt Warren August 14, 2007 # re: LINQ to SQL and attaching Entities I think you guys are misunderstanding how Attach is used. How to deal with a coworker that writes software to give him job security instead of solving problems?

To do so, it needs both the original state of the object and the newly changed state.

So rather than using LINQ directly in the front end UI I want an abstraction layer. So rather than doing an update as above you'd write say a Save() method that does: public bool Save(){ try { context.SubmitChanges(); } catch(Exception ex) { this.SetError(ex); return When you add new records via MGMT Studio does the primary key increment? While testing a new part of the application by deleting one of these items and recreating it, I got this message, even though the item is not in the database anymore.

The resulting steps that you need to solve the problem are therefore: - Remove the relationships from item If the ID=0 then DataContext.Table.InsertOnSubmit(item) DataContext.Table.DeleteOnSubmit(item) You shouldn't actually have to call DataContext.SubmitChanges c# silverlight linq-to-sql windows-phone-7 share|improve this question edited Feb 7 '12 at 18:20 asked Feb 7 '12 at 18:15 Waleed 2,50511528 add a comment| 1 Answer 1 active oldest votes up And yes there is a potential workaround for this particular issue for some scenarios which involves just letting the business object hang on to the DataContext, which frankly is the more http://electrictricycle.net/cannot-attach/cannot-attach-an-entity-that-already-exists-update.html Regards, Tahir. ‹ Previous Thread|Next Thread › This site is managed for Microsoft by Neudesic, LLC. | © 2016 Microsoft.

Note : When I use two different instances of the data context, this behavior disappears. Or maybe create an identity column in the table and make that the primary key? Monday, March 15, 2010 8:41 AM Reply | Quote Answers 0 Sign in to vote I agree that having to create a temporary ParkHelpDatabaseDataContext object just to do these changes shouldn't Assigning a unique representation to equivalent circular queues Is it safe to use cheap USB data cables?

I have managed to work around my problem with a hybrid solution (I'm not sure if it's a very correct way, but seems to work alright). Its a really weird scenario, are you positive it fails on DeleteOn? –eglasius Mar 25 '09 at 20:14 add a comment| up vote 0 down vote try this if your TEntity's As u said there are many unresolved issues and "bugs" that makes things more complicated. priceless :).

Nothing a little Reflection code can't fix. I am new at LINQ to Sql, and I've noticed that the Properties that we need to assign are decorated with the [Column] attribute. The changes include modifying a field value, inserting a new record, deleting a record and submitting changes.Within each item, there is a “Value” property which shows the state of that change* How can I check that the voltage output from this voltage divider is 2.25V?

Roberto May 22, 2008 # re: LINQ to SQL and attaching Entities Great articles, your're right, i encounter the same problem.And MORE, when you have an array of serialized "Products" entity Is it more than one? more hot questions question feed lang-cs about us tour help blog chat data legal privacy policy work here advertising info mobile contact us feedback Technology Life / Arts Culture / Recreation Anyone know what it is?

There are no flaws in the implementation but there is however one catch: you have to be deft enough to use it.API like the one found in linq to sql has Is the English word "ikebana" a suitable translation for "華道"? cheers, imperialx Reply pkellner All-Star 15383 Points 3614 Posts ASPInsidersModeratorMVP Re: Cannot add an entity that already exists. If you don't have identity field to check for ID, then in general always could do: Instead of: ‘If ID=0' Could do: ‘if (DataContext.Table.GetOriginalEntityState(item) == null)' Reply Ron says: 10 June