I have got the following error now 3 times when making changes to existing Order Tag Groups. I changed the Order Tag Group name, mappings, deleted and added order tags all in one step, then got this error when saving. Repeating the same process again appears to work, so not certain what exactly caused it, but it happened 3 times (not on the same order tag group).
The Order Tag Groups were first imported from another database via Database Tools import.
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[General Info]
Application: SambaPOS
Version: 5.2.11
Region: en
DB: SQ
Machine: MARK-PC
User: Mark
Date: 19/08/2018
Time: 17:18
User Explanation:
Mark said ""
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[Exception Info 1]
Top-level Exception
Type: System.Reflection.TargetInvocationException
Message: Exception has been thrown by the target of an invocation.
Source: mscorlib
Stack Trace: at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Delegate.DynamicInvokeImpl(Object[] args)
at System.Windows.Threading.ExceptionWrapper.InternalRealCall(Delegate callback, Object args, Int32 numArgs)
at System.Windows.Threading.ExceptionWrapper.TryCatchWhen(Object source, Delegate callback, Object args, Int32 numArgs, Delegate catchHandler)
Inner Exception 1
Type: System.InvalidOperationException
Message: The operation failed: The relationship could not be changed because one or more of the foreign-key properties is non-nullable. When a change is made to a relationship, the related foreign-key property is set to a null value. If the foreign-key does not support null values, a new relationship must be defined, the foreign-key property must be assigned another non-null value, or the unrelated object must be deleted.
Source: EntityFramework
Stack Trace: at System.Data.Entity.Core.Objects.ObjectContext.PrepareToSaveChanges(SaveOptions options)
at System.Data.Entity.Core.Objects.ObjectContext.SaveChangesInternal(SaveOptions options, Boolean executeInExistingTransaction)
at System.Data.Entity.Core.Objects.ObjectContext.SaveChanges(SaveOptions options)
at System.Data.Entity.Internal.InternalContext.SaveChanges()
at System.Data.Entity.Internal.LazyInternalContext.SaveChanges()
at System.Data.Entity.DbContext.SaveChanges()
at Samba.Infrastructure.Data.SqlData.EFWorkspace.CommitChanges()
at Samba.Presentation.Common.ModelBase.EntityCollectionViewModelBase`2.<.ctor>b__0_3(EventParameters`1 x)
at Microsoft.Practices.Prism.Events.EventSubscription`1.InvokeAction(Action`1 action, TPayload argument)
at Microsoft.Practices.Prism.Events.EventSubscription`1.<>c__DisplayClass2.<GetExecutionStrategy>b__0(Object[] arguments)
at Microsoft.Practices.Prism.Events.EventBase.InternalPublish(Object[] arguments)
at Microsoft.Practices.Prism.Events.CompositePresentationEvent`1.Publish(TPayload payload)
at Samba.Presentation.Services.Common.ExtensionMethods.Publish[TEventsubject](TEventsubject eventArgs, String eventTopic, Action expectedAction)
-----------------------------
[Assembly Info]
mscorlib, Version=4.0.0.0
Samba.Services, Version=1.0.0.0
Samba.Domain, Version=1.0.0.0
Samba.Infrastructure.Data, Version=1.0.0.0
System.ComponentModel.Composition, Version=4.0.0.0
Samba.Presentation.Services, Version=1.0.0.0
System.Core, Version=4.0.0.0
PresentationCore, Version=4.0.0.0
DevExpress.Xpf.LayoutControl.v16.2, Version=16.2.6.0
System.Xml, Version=4.0.0.0
DevExpress.Xpf.Grid.v16.2, Version=16.2.6.0
System, Version=4.0.0.0
DevExpress.Xpf.Grid.v16.2.Core, Version=16.2.6.0
WindowsBase, Version=4.0.0.0
System.Xaml, Version=4.0.0.0
PresentationFramework, Version=4.0.0.0
Samba.Infrastructure, Version=1.0.0.0
Microsoft.Practices.Prism, Version=4.0.0.0
System.Runtime.Serialization, Version=4.0.0.0
Microsoft.Practices.Prism.MefExtensions, Version=4.0.0.0
DevExpress.Xpf.Core.v16.2, Version=16.2.6.0
System.Windows.Forms, Version=4.0.0.0
System.Drawing, Version=4.0.0.0
Samba.Persistance, Version=1.0.0.0
Stateless, Version=1.0.0.0
PropertyTools, Version=2012.4.14.1
Samba.Localization, Version=1.0.0.0
ReachFramework, Version=4.0.0.0
EntityFramework, Version=6.0.0.0
FluentValidation, Version=3.4.0.0
Microsoft.CSharp, Version=4.0.0.0
Omu.ValueInjecter, Version=2.3.0.0
Microsoft.Practices.ServiceLocation, Version=1.0.0.0
DevExpress.Data.v16.2, Version=16.2.6.0
NCalc, Version=1.3.8.0
WindowsInput, Version=1.0.4.0
-----------------------------
[System Info]
Operating System
-Microsoft Windows 10 Pro
--CodeSet = 1252
--CSDVersion =
--CurrentTimeZone = 60
--FreePhysicalMemory = 8040156
--OSArchitecture = 64-bit
--OSLanguage = 2057
--ServicePackMajorVersion = 0
--ServicePackMinorVersion = 0
--Version = 10.0.17134
Machine
-MARK-PC
--Manufacturer = Gigabyte Technology Co., Ltd.
--Model = To be filled by O.E.M.
--TotalPhysicalMemory = 17068531712
--UserName = Mark-PC\Mark
-----------------------------