nhibernate - mapping with contraints
- by Tobias Müller
Hello everybody,
I am having a Problem with my nhibernate-mapping and I can't find a solution by searching on stackoverflow/google/documentation.
The database I am using has (amongst others) two tables. One is unit with the following fields:
id
enduring_id
starts
ends
damage_enduring_id
[...]
The other one is damage, which has the following fields:
id
enduring_id
starts
ends
[...]
The units are assigned to a damage and one damage can have zero, one or more units working on it. Every time a unit moves to annother damage, the dataset is copied. The field "ends" of the old record and "starts" of the new record are set to the current time stamp, enduring_id stays the same. So if I want to know which units were working on a damage at a certain time, I do the following select:
select * from unit join damage on damage.enduring_id = unit.damage_enduring_id where unit.starts <= 'time' and unit.ends = 'time'
(This is not an actualy query from the database, I made it up to make clear what I mean. The the real database is a little more complex)
Now I want to map it that way, so I can load all the damages which are valid at one time (starts <= wanted time <= ends) and that each of them has a Bag with all the attached units at that time (again starts <= wanted time <= ends).
Is this possible within the mapping?
Sorry if this is a stupid question, but I am pretty new to nhibernate and I have no clue how to do it.
Thanks a lot for reading my post!
Bye,
Tobias