Hello,

I've two tables in a single database : Products and Customers. They are mapped to the classes Product and Customer.
I would like to load, modify and update the data from the both tables separately (i.e not at the same time).

For example, I would like to :
- first, load the data from Products
- then execute some code with the objects of type Product
- then load the data from Customers
- then upload the modifications from the object of type Product to the db.
- then execute some code with the objects of type Customers
- then upload the modifications from the object of type Customers to the db.

How can I achieve this ? Is it possible to open several transaction in a single session ?

You can evict objects from the session, but then you have to save them again:

session.Evict(obj);
...
work on the ojects
...
foreach changed object
session.Update();

In this scenario, you have to check manually if the objects have changed, otherwise you get unnecessary updates to the db.

Can't you use two sessions ? That would be a much nicer and cleaner way to solve that. But I guess you wouln't have asked, if you could.