Hi,

When I save an object that has empty int variables, those get saved into the DB as 0, not as null. Where can I make a change to get NHibernate to save the record with a null value?

Thanks,
Jerry

What do you mean for "empty int"? An int variable cannot be empty, it can be only a valid number.
I think that if the column can be null you must use a Nullable type.
Try to declare your property and variable type like this: int?

In this way the property accepts also null values.

Davide

If I have a class:

Whenever I try to read a record from the DB where age has a NULL value in the DB, NHibernate assigns 0 for the age variable. Same thing happens when saving an unassigned age variable, the DB get's a 0.
I need to get and save NULLs instead of 0 for unassigned age, as returning or saving a 0 into the DB isn't the correct value, because the Cat might by 5 years old not 0 and I have just left that value out; therefore I'm storing and working with an incorrect age.
Would normal practice be, instead of using "private int age" to use "private Int32 age"? Or what's the recommended way to work with such data?

Thanks

Try with this (using Nullable values):



Davide

Tried the "int?" type, and now I get this message:

Do I need to make a change anywhere else besides that class?

As I known you don't need any special configuration. For more information try to look at this link:
http://www.hibernate.org/hib_docs/nhibe ... ml_single/
and search for "Nullable<Int32>"

Consider that nullable types are supported only NHibernate 1.2 I think.

Davide

.NET 2.0 Nullables works just fine in 1.0.3
Just set "type" attribute for property mapping to "non-nullable type"
See example....

Class:


Mapping:

After migrating to NHibernate 1.2, the "int?" nullable works perfectly. Thank you very much for your help Davide. :)
Liwoj, if I had known that it would work in 1.0.3 a bit sooner it would have saved me a big headache when migrating (wasn't easy :) ), but at least I've got the newest version of NHibernate now :)

Thanks,
Jerry