i have some puzzle with "many-to-one", "one-to-many", "many-to-many"

now, i use the mapping files without such as "many-to-one",
so i can use HQL expression like SQL .

for example ,

if the mapping without "many-to-one"
i can write code as :
select a.m, a.x, b.y from A a, B b where a.m=b.m and a.n=b.n

a.m , a.n is a foreign key , b.m and b.n is a composite primary key

but
the mapping file for table A created by middlegen has element "many-to-one". and class A has no field name like "m" or "n"

so i can't write HQL like
"select a.m, a.x, b.y from A a, B b where a.m=b.m and a.n=b.n"
because Class A for table A has no property named "m"

i think that isn't intuitionistic. and perhaps it will effect replantting.

>>>i've write many codes with mapping without "many-to-one".
if i change to use "many-to-one" , i seems i must rewrite the codes.
i don't want to do that. is there anything i did wrong. or there has a better solution?

>>> i don't know how to ask this question better. i wish someone could understand what i means.

If you map the reationship then Hibernate can automatically load the relationship data and populate the Java Classes for you. You can use a query as well (depending on the database and lazy settings if might not any more efficient). An OR mapper allows you to think more about you Java domain model rather than the relational model.