do this:
db.define.table('basic'
Field('name1')
...,format='%(name1)s')
db.define.table('advanced'
Field('name2',db.basic)
...,format='%(name2)s')
# db.advanced.name.requires=IS_IN_DB(db,'basic.id','%(name1)s')
db.define.table('data'
Field('something',db.advanced)
...)
