Home → Help and guidance →

Setting Component as Unique Key

sks

12 May, 2010 08:19 PM via web

Admin Functions

• Edit
• Remove

This may be a very simple question. I am running on Build# 650 of FluentNHibernate.
I am trying to set the Address component below as Unique key.

public class Employee 
{ 
  [DomainSignature] 
  public Address MailingAddress { get; set;} 
} 

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

I am trying to use IComponentConvention to do this and here is what I am doing:

public class ComponentConvention : IComponentConvention 
{ 
        public void Apply(IComponentInstance instance) 
        { 
                if (Attribute.IsDefined(instance.Property.MemberInfo, typeof(NaturalKeyAttribute))) 
                { 
                        foreach (var property in instance.Properties) 
                        { 
                                property.UniqueKey("NaturalKey"); 
                        } 
                } 
        } 
}

The problem is when I run the Mapping tests on Employee , I don't see the code entering ComponentConvention at all, so hence it is never translated as Unique keys in the database table. On the other hand, if I use an older build (Build# 633), I get the
code to enter ComponentConvention, but it doesn't have a settable UniqueKey. Am I doing something wrong here or is there a different approach to solve this problem.

Thanks,
sks

1. Support Staff 2 Posted by James Gregory on 16 May, 2010 04:53 PM

   

   You're going to have to give us some more information. How are you mapping your classes? Automapping or ClassMap? Are you using ComponentMap to map your component?

   Admin Functions

   • Edit
   • Remove

2. 3 Posted by sks on 17 May, 2010 04:18 PM

   

   We are using ClassMap. Below is an example of our EmployeeMap.

   public sealed class EmployeeMap : ClassMap
   {

   public EmployeeMap()
   {       
       Component(x => x.Address)
           .ColumnPrefix("Mailing");
   }
   

   }

   Here is our AddressMap.

   public class AddressMap : ComponentMap

   
   {
   
   

   public AddressMap()
   {
       Map(x => x.Street);
       Map(x => x.City);
   }
   

   }

   We added the below convention so that we can make the MailingAddress properties part of a unique constraint in the database if there
   is a [DomainSignature] attribute on the MailingAddress component.

   public class ComponentConvention : IComponentConvention
   {

   public void Apply(IComponentInstance instance) 
   { 
           if (Attribute.IsDefined(instance.Property.MemberInfo,typeof(DomainSignatureAttribute))) 
           { 
                   foreach (var property in instance.Properties) 
                   { 
                           property.UniqueKey("DomainSignature"); 
                   } 
           } 
   }
   

   }

   With the above convention, we are trying to get NHibernate to generate a unique constraint (DomainSignature) on Street and City in the Employee table.

   Thanks,
   sks

   Admin Functions

   • Edit
   • Split
   • Remove

3. 4 Posted by juggernaut78 on 02 Dec, 2010 09:33 PM

   

   Is this a known issue for the IComponentConvention, that Apply is never called? I have same issue with FNH 1.1. Attaching simple repro solution for vstudio 2010.
   Expected output from Tests\MappingTest.CanExportDbSchemaWithComponentPrefix :
   a db schema output with prefixes for component address columns.
   Actual output: no prefixes for the columns.
   (Apply method is never called).

   • ComponentConvention.rar 1.4 MB

   Admin Functions

   • Edit
   • Split
   • Remove