LINQ to EF4 Query Where子句未按预期进行过滤

Question

I've googled for this but can't find anything obviously related, so posting here for some insight. Using LINQ / EF4. Here's the code snippet:

 private const string JOB_FAILED = "Failed";
// other code..

var successfulJobs = context.Jobs.Where(x => x.Status != JOB_FAILED);
                foreach (Job successfulJob in successfulJobs)
                {
                    context.DeleteObject(successfulJob);
                }

I would expect successfulJobs to contain all jobs where Job.Status != "Failed". However, the code witihn foreach{} executes when Job.Status DOES equal "Failed". Am I missing something fundamental here about LINQ\\Lambda?

EDIT: Generated SQL as requested, seems ok.

SELECT 
[Extent1].[Id] AS [Id], 
[Extent1].[Parameters] AS [Parameters], 
[Extent1].[Status] AS [Status], 
[Extent1].[Created] AS [Created], 
[Extent1].[Modified] AS [Modified]
FROM [bws].[JobRunner_Tasks] AS [Extent1]
WHERE N'Failed' <> [Extent1].[Status]

Answer 1

hmmmm.... in any other language, I might suggest using

x => !x.Status.equals(JOB_FAILED)

but I didn't think string comparison was that finicky in C#

Answer 2

I would still say it's a case sensitive issue. What does the query return if you run it directly in SQL? Can you maybe post a sample of the data in that table? (Including "Failed" statuses) I know this isn't an answer but i can't add comments to the post yet (rep below 50).