Specifies that the type family of the type is not polymorphic - the type family contains a single class.
Mapping the
type with
<Sealed> element
means declaring that the type has no descendants. The C#
class modifier sealed
cannot be used for persistent classes because
Genome
creates inherited classes from
the type to implement proxies.
<Sealed> element
also means that the dynamic type of an instance persisted
to the database is always the type.
As opposed to the <TypeDiscriminator> element , this type identity provider does not demand that additional fields are defined in the database table for identity. Therefore, it provides a solution for mapping existing databases. The overhead of handling polymorphism and an additional field is eliminated.
The class Employee has no descendants.
<Type name="Employee">
<RootInheritance /> <Sealed /> ... </Type>
Type: TechTalk.Genome.Mapping.SealedXmlData
Assembly: TechTalk.Genome.dll
Version: 4.2.4
Editions: Professional, Evaluation, Express
Database Platforms: Microsoft SQL Server 2000, Microsoft SQL Server 2005, Oracle 9i Release 2, Oracle 10g Release 2