FluentNHibernate Component.ColumnPrefix not being

问题:

I recently upgraded FluentNHibernate from v1.1.0.685 to v1.2.0.712 (latest) for NHibernate 2.1.

My issue appears to be with classes that use the Component().ColumnPrefix() mapping.

For example,

 public class Address{ 
    public string Street {get; set;} 
    public string Zip {get; set;} 
 } 

 public class AddressMap : ComponentMap<Address>{
     Map( x => x.Street );
     Map( x => x.Zip );
 }

 public class PersonMap : ClassMap<Person> 
 { 
    public PersonMap(){ 

       Id( x => x.Id ); 

       Map( x=> x.Name ); 

       Component( x => x.Address ) 
          .ColumnPrefix("ADDRESS_"); 
    } 
 } 

Person Table

  Id       Name        ADDRESS_Street     ADDRESS_Zip
 ----------------------------------------------------
  1        Brian       123 Example St.    12345

Behavior in FNH v1.1.0.685

The "ADDRESS_" prefix is correctly applied to the properties of the Address component.

Behavior in FNH v1.2.0.712 (latest)

The "ADDRESS_" prefix is no longer applied to the properties of the Address component. NHiberante generates "Street" and "Zip" columns which are not named in table above.

---

I'd appreciate if anyone has any insight. I'm beginning to think this might be a bug.

Thanks,
Brian

回答1:

@Brian,

I hit the exact roadblock a few weeks ago. I'm using automappings and got around it by creating a Component Property Convention:

Public Class ComponentPropertyConvention
    Implements IPropertyConvention, IPropertyConventionAcceptance

    Public Sub Accept(ByVal criteria As IAcceptanceCriteria(Of IPropertyInspector)) Implements IConventionAcceptance(Of IPropertyInspector).Accept
       criteria.Expect(Function(inspector) inspector.EntityType.Namespace.EndsWith("Components"))
    End Sub

    Public Sub Apply(ByVal instance As IPropertyInstance) Implements IConvention(Of IPropertyInspector, IPropertyInstance).Apply
        instance.Column(String.Format("{0}_{1}", New String() {instance.EntityType.Name.ToLower(), instance.Property.Name.Dbize()}))
    End Sub

End Class

There's probably a wealth of ways to implement your acceptance criteria so don't follow mine if it doesnt suit...

Cheers

回答2:

After investigating the unit tests in the source code; it appears that, in my case, my conventions were being applied differently between FNH v1.1 and FNH v1.2.

I think this is what happened:

1. My AddressMap : ComponentMap<Address> would get executed (no problem here).

2. My PersonMap : ClassMap<Person> would map a component using:

   Component( x => x.Address ).ColumnPrefix("ADDRESS_"); 
   

   from Step 1.

3. My FNH MyPropertyConvention would call:

   public class MyPropertyConvention : IPropertyConvention
   {
       public void Apply( IPropertyInstance instance )
       {
           instance.Column( instance.Name ); //this call is destructive
                                             //to ColumnPrefix() in FNH v1.2
       }
   }
   

It appears:

• in FNH v1.1, Step 3 is not destructive to the column prefix when calling instance.Column().

• in FNH v1.2, Step 3 is destructive to any ColumnPrefix() previously set and over-writes the entire column name (including the prefix).

So, I cleaned up my conventions for FNH 1.2 using IPropertyConventionAcceptance being careful about my calls to instance.Column(instance.Name) [now that calls are destructive to column prefixes].

Thanks for everyone's help,
Brian

回答3:

You need to create a ComponentMap<Address> class in order for the ColumnPrefix to be applied.

See here: http://wiki.fluentnhibernate.org/Fluent_mapping#ComponentMap.3CT.3E