空表上的System.Data.Linq.DuplicateKeyException

Question

I get this error:

System.Data.Linq.DuplicateKeyException: Cannot add an entity with a key that is already in use.

When I run this code, which walks a directory and puts associated records in a database.

   public string RefreshClientTable(string username, string companyName) {
        string company_path = @"M:/" + companyName + "/Clients/";
        string info = "";
        ExplorerBAL b = new ExplorerBAL();
        List<Explorer.DirModel> c = b.Explorer(company_path).dirModelList;
        DataContext dbContext = new BaseDataContext();
        var db_company_clients = dbContext.Clients.Where(d => d.co_name == companyName).ToList();
        foreach (var client_name in c) {
            //Determine if client exists
            info = info + "Found: " + client_name.DirName + "\n";
            int client_in_db = dbContext.Clients.Count(f => f.co_name == companyName && f.cl_name == client_name.DirName);
            if (client_in_db == 1) {
                //Update ancillary fields (later)
            }
            else {
                info = info + "Updating: " + client_name.DirName + "\n";
                //Insert the record if non-existant
                Project insert_sql = new Project() {
                    co_name = companyName,
                    cl_name = client_name.DirName
                    //Update ancillary fields (later)
                };
                dbContext.Projects.InsertOnSubmit(insert_sql);
            }
        }

        try {
            dbContext.SubmitChanges();
            return "SUCCESS:\n" + info;
        }
        catch (Exception e) {
            return "ERROR:\n" + info + e.ToString() + "\n";
        }
    }

Note that the tables are empty and the primary keys are two varchar fields. Based on research I suspect its some kind of an issue with the multiple calls to dbContext. I suspect it would work if I wasn't first checking for the existing of the item, but I really need to do that.

Does any one know anything about this issue? There are similar questions, but no suitable answers... yet inserting into a table is a very common operation so something must be very specifically wrong.

Answer 1

Well, I hate to solve an 8 hour long problem with a typo solution. But here it is:

dbContext.Projects.InsertOnSubmit(insert_sql);

should have been:

dbContext.Clients.InsertOnSubmit(insert_sql);

Copy/paste error