although you have used tablea.*, it will give you all records based on join condition
select tablea.* from tablea,tableb where tablea_pk = tableb_fk
select tableb.* from tablea,tableb where tableb_pk = tablea_fk
If you want distinct data then try the following:
select distinct a.field1, a.field2 from tablea a, tableb b where a.table_pk = b.table_pk