Invalid column name 'CreatedOn' about dotnet

[yellis]

What were you doing when you got this message? Are you saving results to Sql?

[Yustie]

I'm starting my web application and than It breaks with that exception when its still loading the browser.
I'm guessing that miniprofiler expects a column createdOn, while there isn't any.

[yellis]

CreatedOn does not appear in the MiniProfiler code base.

My guess is that your Entity Framework data context has a CreatedOn column in some table and your database does not, and the MiniProfilerEF.Initialize() function is causing an error to occur because of this.

Do you have CreatedOn anywhere in your data context?

[Yustie]

CreatedOn used to be a column in version 4.xx (or something) in EF. As of version 5 that was no longer the case. I'm at 6 and there is no such column in any of my models or the migrationhistory table.

[yellis]

Well, it's coming from somewhere in your code (it definitely isn't from MiniProfiler).

[Yustie]

Check the first comment on this post: http://stackoverflow.com/questions/11979026/entity-framework-5-expects-createdon-column-from-migrationhistory-table
Do you have access to the link in that first comment? It's either deleted or private. But related to this issue.

[yellis]

It points here

[oleneveu]

I'm experiencing exactly the same problem (.ef6 3.0.10-beta5, .net 4.0)
It happens when initializing my dbcontext in Application_Start().
If I remove MiniProfilerEF6.Initialize(), everything works fine. If I add the column CreatedOn to the __MigrationHistory table, it works once. Next time the column has been removed by EF and the exception throws again...

[Yustie]

@oleneveu, yellis is pretty hardheaded, I don't think he will look into it. He's very convinced it's our code. Also, he closes issues instantly.

Try this post on SO: http://stackoverflow.com/questions/23587321/miniprofiler-breaks-on-missing-createdon-column

[yellis]

Can either of you give code (preferably a full solution zipped or pushed to a rep - even better if you can reproduce this in a fork of Sample.Mvc) that can be used to replicate this?

I believe you that it is happening but cannot reproduce it.

[oleneveu]

I have provided some information on the SO post. I will try to provide a project to reproduce the problem if I have enough time...

[yellis]

To clarify - is this only happening when you run in VS in debug mode? Does it show up in non-debug mode or on prod?

All of the solutions that I have seen revolve around either adding a CreatedOn column to __MigrationHistory, turning off change tracking or not throwing this exception in the debugger. Well how about we just swallow this exception in MiniProfilerEF6.Initialize() - the same way that we are doing right now for a similar error with column "ContextKey"?

This error itself seems to be pretty innocuous and is indicative of some weird leftover issue from EF 4.3 >> EF 5 that is triggered by the way we are tapping into EF6 here, so just ignoring the error doesn't seem like it will cause any harm.

Thoughts?

[oleneveu]

I can provide a sample project to reproduce the problem. You can download the zip here:
http://peuplier.i234.me:80/fbsharing/1NRKeqDK
I have removed all binaries, you will have to restore nuget packages.
It seems that EF migrations have to be enabled for the problem to occur. This sample uses SqlCE 4, it might also be related to it...

The break occurs in Application_Start() (see the comment).

[oleneveu]

You are right, this is not a real error but just a break that occurs for a reason that I could not find. I have spent some time searching for the code that could be in cause (System.Diagnostics.Debugger.Break();?) without success.
When running outside of the debugger, everything works fine...

[yellis]

Ok, I am able to replicate it. This does correspond to the section of code that @oleneveu posted on SO. The EF code here is designed to try out a legacy migration method, and if it catches an error it doesn't do anything with it (the whole purpose of doing this is to see if a CreatedOn column exists, and if so, to drop it first). As others have said, you can avoid this by manually creating a CreatedOn column but this will be dropped every time, so that is not so practical.

The issue itself is within the EntityFramework code, where (I believe) they are catching an EntityException when trying out this code. When this is accessed through EntityFramework without MiniProfiler, it catches the EntityException, because the __MigrationHistory table is being accessed through Entity Framework. However, when MP intercepts this command and runs it through a ProfiledDbCommand, it throws a DbException when it fails, not an EntityException, and if you are set to catch these (as you are by default) in debug mode, then you know what happens.

Potential solutions:

1. Submit a PR to EntityFramework to add catch (DbException) {} to this section of code
2. Ignore the Exception using the solution given by @oleneveu in his SO answer.
3. Don't use EF Migrations

I just spent some time trying to trap and catch the exception in different ways within the MP.EF6 code, and each time the user-unhandled exception from EntityFramework was still caught and thrown by Visual Studio (until doing option 2 above).

At this point, since it is a debug-only issue and I do not have a way to prevent it from happening in EF6 using our method of initializing MiniProfiler for EF6, I do not see any code changes happening in the MP.EF6 code to address this issue, and the potential solutions above are my recommendations for how to proceed if this issue is occurring for you.

[oleneveu]

I think that the problem may be related to the fact that the PDB files are included in the NuGet packages. I have noticed that if I remove the MiniProfiler PDB files, the break does not occurs anymore.
I have edited my SO answer to provide another workaround.