EF6 - Error inserting 2 related objects in a single SaveChanges

[Samuel Sippe]

*** Also posted to stackoverflow which is a bit easier to read for the formatting
http://stackoverflow.com/q/22138579/176868
***

Hi,

I am attepting to insert two related objects Client and Quote (where Quote has a Client) in a single call to save changes. Code is:

                      
            var client = new Client();
            db.Client.Add(client);            
            var quote = new Quote();
            quote.Client = client;
            db.Quote.Add(quote);

            db.SaveChanges();
 
Exception is:

Additional information: An error occurred while updating the entries. See the inner exception for details.

   at System.Data.Entity.Internal.InternalContext.SaveChanges()
   at System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
   at System.Data.Entity.DbContext.SaveChanges()
  at MyTestClass... 

Inner Exception is:
{"The specified value is not an instance of a valid constant type.\r\nParameter name: type"}

   at System.Data.Entity.Core.Mapping.Update.Internal.UpdateTranslator.Update()
   at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.<Update>b__2(UpdateTranslator ut)
   at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.Update[T](T noChangesResult, Func`2 updateFunction, Boolean throwOnClosedConnection)
   at System.Data.Entity.Core.EntityClient.Internal.EntityAdapter.Update(Boolean throwOnClosedConnection)
   at System.Data.Entity.Core.Objects.ObjectContext.<SaveChangesToStore>b__33()
   at System.Data.Entity.Core.Objects.ObjectContext.ExecuteInTransaction[T](Func`1 func, IDbExecutionStrategy executionStrategy, Boolean startLocalTransaction, Boolean releaseConnectionOnSuccess)
   at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesToStore(SaveOptions options, IDbExecutionStrategy executionStrategy)
   at System.Data.Entity.Core.Objects.ObjectContext.<>c__DisplayClass28.<SaveChanges>b__25()
   at System.Data.Entity.Infrastructure.DefaultExecutionStrategy.Execute[TResult](Func`1 operation)
   at System.Data.Entity.Core.Objects.ObjectContext.SaveChanges(SaveOptions options)
   at System.Data.Entity.Internal.InternalContext.SaveChanges()



Entity classes:

    public class Client
    {
        [Key]
        public long Id { get; set; }
        ....
    }

    public class Quote
    {
    
        [Column("id")]
        [Key]
        public long Id { get; set; }
   
        [Column("client")]
        [ForeignKey("Client")]
        public long ClientId { get; set; }

        public virtual Client Client { get; set; }
        ...
   }


Libraries:
EF6
MySql.Data.dll v6.8.3
MySql.Data.Entity.EF6.dll v6.8.3

If I add a db.SaveChanges() after the db.Client.Add(client) line, it will work ok but I want to use the unit of work pattern on group database calls where possible. Any ideas what could be going wrong?



Edited 2 time(s). Last edit at 03/04/2014 04:33PM by Samuel Sippe.