I am using Fluent NHibernate to define the models and mappings. I am also fairly new to hibernate so please pardon my ignorance :)

For an object like one below:
> Entity
- int ID (Identity)
- string Name
- OtherInfo
> Attribute
- int ID
- string Name (Unique Key)
- Other info
> Entity_Attribute
- int ID
- int EntityID (FK to Entity)
- AttributeID (FK to Attribute)
- Value

I have the mappings well defined and I am able add new entities, attributes and entity_attribute. But what I was wondering was if there is a way (fluent/interceptor/listener) to add an object (such as attribute or entity_attribute) if it doesn't exist in database otherwise reference the existing one.

Something which can represented by following query:

> Attribute query
if exists(select id from attribute where name=@Name)
begin
insert attribute query
select scope_Identity()
end
else
begin
select attribute's id
end
> Entity Attribute query
if exists (select id from entity_attribute where attributeid=@attributeid and entityid=@entityid)
begin
insert entity_attribute query
select scope_identity
end
else
begin
update entity_attribute query
select id from entity_attribute
end

Ignore. I figured it out myself.