Members (properties and methods) of any type (persistent and non persistent) can be mapped with member mappings so that they can be executed in the underlying relational database system. Only those members of a type that are executed in the underlying relational database system have to be mapped in the schema definition file. Member mappings specify the translation of member calls to SQL in the underlying relational database system.
The <Oql> element defines the translation of the members into an OQL expression.
The <RawSql> element can be used to map members to special platform-specific features as it gives low-level access to the underlying relational database system. It specifies the translation of the members as a raw SQL snippet expression.
<Oql> Element | <RawSql> Element