Hi Mani
It allows user-defined types in the SQL standard way by using "CREATE TYPE" to register a type (http://pubs.vmware.com/vfabric5/index.jsp?topic=/com.vmware.vfabric.sqlfire.1.0/developers_guide/topics/udt/cdevspecialudt.html). The type must implement java.io.Serializable (Externalizable for better performance). Then the type can be used in procedure args, table column types etc. (normally anywhere an inbuilt type can be used). Simple example:
CREATE TYPE mytype EXTERNAL NAME 'examples.mytype' LANGUAGE JAVA
Now mytype can be used in most places where inbuilt types can be. The class can also be one installed dynamically in the system using sqlj.install_jar.
thanks
sumedh