What you need is called typed-tables in DB2. For global information about inheritance: http://pic.dhe.ibm.com/infocenter/db2luw/v10r5/topic/com.ibm.db2.luw.admin.structypes.doc/doc/c0006588.html
You first need to create a structure (type), and then you can use that structure in a table.
Please, check this first (http://pic.dhe.ibm.com/infocenter/db2luw/v10r5/topic/com.ibm.db2.luw.admin.structypes.doc/doc/c0006441.html) read all sections and them proceed with your own implementation.