Entity Framework: “Store update, insert, or delete

Question

I am using Entity Framework to populate a grid control. Sometimes when I make updates I get the following error:

Store update, insert, or delete statement affected an unexpected number of rows (0). Entities may have been modified or deleted since entities were loaded. Refresh ObjectStateManager entries.

I can't figure out how to reproduce this. But it might have something to do with how close together I make the updates. Has anyone seen this or does anyone know what the error message refers to?

Edit: Unfortunately I am no longer at liberty to reproduce the problem I was having here, because I stepped away from this project and don't remember if I eventually found a solution, if another developer fixed it, or if I worked around it. Therefore I cannot accept any answers.

Answer 1

Well i have this same issue. But this was due to my own mistake. Actually i was saving an object instead of adding it. So this was the conflict.

Answer 2

I was having same problem and @webtrifusion's answer helped find the solution.

My model was using the Bind(Exclude) attribute on the entity's ID which was causing the value of the entity's ID to be zero on HttpPost.

namespace OrderUp.Models
{
[Bind(Exclude = "OrderID")]
public class Order
{
    [ScaffoldColumn(false)]
    public int OrderID { get; set; }

    [ScaffoldColumn(false)]
    public System.DateTime OrderDate { get; set; }

    [Required(ErrorMessage = "Name is required")]
    public string Username { get; set; }
    }
}   

Answer 3

One way to debug this problem in an Sql Server environment is to use the Sql Profiler included with your copy of SqlServer, or if using the Express version get a copy of Express Profiler for free off from CodePlex by the following the link below:

Express Profiler

By using Sql Profiler you can get access to whatever is being sent by EF to the DB. In my case this amounted to:

exec sp_executesql N'UPDATE [dbo].[Category]
SET [ParentID] = @0, [1048] = NULL, [1033] = @1, [MemberID] = @2, [AddedOn] = @3
WHERE ([CategoryID] = @4)
',N'@0 uniqueidentifier,@1 nvarchar(50),@2 uniqueidentifier,@3 datetime2(7),@4 uniqueidentifier',
@0='E060F2CA-433A-46A7-86BD-80CD165F5023',@1=N'I-Like-Noodles-Do-You',@2='EEDF2C83-2123-4B1C-BF8D-BE2D2FA26D09',
@3='2014-01-29 15:30:27.0435565',@4='3410FD1E-1C76-4D71-B08E-73849838F778'
go

I copy pasted this into a query window in Sql Server and executed it. Sure enough, although it ran, 0 records were affected by this query hence the error being returned by EF.

In my case the problem was caused by the CategoryID.

There was no CategoryID identified by the ID EF sent to the database hence 0 records being affected.

This was not EF's fault though but rather a buggy null coalescing "??" statement up in a View Controller that was sending nonsense down to data tier.

Answer 4

Just make sure table and form both have primary key and edmx updated.

i found that any errors during update were usually because of: - No primary key in Table - No primary key in Edit view/form (e.g. @Html.HiddenFor(m=>m.Id)

Answer 5

I started getting this error after changing from model-first to code-first. I have multiple threads updating a database where some might update the same row. I don't know why I didn't have a problem using model-first, assume that it uses a different concurrency default.

To handle it in one place knowing the conditions under which it might occur, I added the following overload to my DbContext class:

using System.Data.Entity.Core.Objects;
using System.Data.Entity.Infrastructure;

public class MyDbContext: DbContext {
...
        public int SaveChanges(bool refreshOnConcurrencyException, RefreshMode refreshMode = RefreshMode.ClientWins) {
            try {
                return SaveChanges();
            }
            catch (DbUpdateConcurrencyException ex) {
                foreach (DbEntityEntry entry in ex.Entries) {
                    if (refreshMode == RefreshMode.ClientWins)
                        entry.OriginalValues.SetValues(entry.GetDatabaseValues());
                    else
                        entry.Reload();
                }
                return SaveChanges();
            }
        }
}

Then called SaveChanges(true) wherever applicable.

Answer 6

I had the same problem. In my case I was trying to update the primary key, which is not allowed.