Question

Given the two Entities ProcessTemplateOperation and ProcessTemplateMetaInformation with a relation 1 to 0..1

When I add a ProcessTemplateOperation which HAS a ProcessTemplateMetaInformation I get the following error at Context.ApplyChanges (in EF it is in AddHelper.AddAllEntities: context.AddObject)

Multiplicity constraint violated. The role ‘ProcessTemplateOperation’ of the relationship
‘…FK_ProcessTemplateOperation_MetaInformation’ has the multiplicity 1 or 0..1.

The debugger staying in the EntityFramework code says that the Operation has a Metainformation, so it is not lost on the way.

The definition of the RelationShip is

      <AssociationSet Name="FK_ProcessTemplateOperation_MetaInformation" Association="FireStartDBModel.Store.FK_ProcessTemplateOperation_MetaInformation">
        <End Role="ProcessTemplateOperation" EntitySet="ProcessTemplateOperation" />
        <End Role="ProcessTemplateMetaInformation" EntitySet="ProcessTemplateMetaInformation" />
      </AssociationSet>

    <Association Name="FK_ProcessTemplateOperation_MetaInformation">
      <End Role="ProcessTemplateOperation" Type="FireStartDBModel.Store.ProcessTemplateOperation" Multiplicity="1">
        <OnDelete Action="Cascade" />
      </End>
      <End Role="ProcessTemplateMetaInformation" Type="FireStartDBModel.Store.ProcessTemplateMetaInformation" Multiplicity="0..1" />
      <ReferentialConstraint>
        <Principal Role="ProcessTemplateOperation">
          <PropertyRef Name="Id" />
        </Principal>
        <Dependent Role="ProcessTemplateMetaInformation">
          <PropertyRef Name="Id" />
        </Dependent>
      </ReferentialConstraint>
    </Association>

      <AssociationSet Name="FK_ProcessTemplateOperation_MetaInformation" Association="FireStartDBModel.FK_ProcessTemplateOperation_MetaInformation">
        <End Role="ProcessTemplateOperation" EntitySet="BaseOperation" />
        <End Role="ProcessTemplateMetaInformation" EntitySet="BaseMetaInformation" />
      </AssociationSet>

And there is a NavigationProperty from the ProcessTemplateOperation but NO Navigation property on ProcessTemplateMetaInformation.

We are using TPC and ProcessTemplateOperation has a Base class BaseOperation and a derived class ProcessOperation…

Thanks for any help!

Answer 1

We solved the issue.

We had some Navigationproperties which were running in a circle.

We removed them and everything works fine now!