/* Formatted on 2008/09/30 21:07 (Formatter Plus v4.8.7) */ SELECT isa.per_name || ' ist ein ' || relation_type.ret_name ||' von '|| persons.per_name FROM persons, relations, persons isa, relation_type WHERE ( (persons.per_id = relations.rel_parent) AND (isa.per_id = relations.rel_child) AND (relation_type.ret_id = relations.rel_ret_id) )
insert
insert into relations ( REL_ID, REL_PARENT, REL_CHILD, REL_RET_ID) values ( sim.nextval, (select per_id from persons where per_name = 'Bart'), (select per_id from persons where per_name = 'Homer'), (select ret_id from relation_type where ret_name = 'Elternteil'));