Hi.

If I have a table like TableA with ID, NAME, BINARY columns how can I retrive the TableA object without BINARY data ?

Is this query string appropriate:
select a.ID as {a.Id}, a.NAME as {a.Name} from TableA as a?

Tnx
markov

can no one answer this question?

cause if i dont define binary field in my sql statement i get the exception from hibernate? is there any way to set no needed fields to null?

tnax
markov

The TableA object will return all the properties it has mapped to database columns. If you want to return only specific columns/properties, you have two choices.



or



This assumes that the MiniTableA object has the appropriate constructor signature, and has been included in the mappings.

http://www.hibernate.org/hib_docs/nhibernate/html/queryhql.html

This is a common question. I tried searching the forums to give you a link to previous questions, but oddly enough my searches returned no results.

hmmm, i never thought of defining a new mini object...i'll consider that. but i hoped it is posible to get the table object back but with only certain fields filled. like if you have a table with some fields containing binary data maybe you dont want allways to get that binary data but just some other fileds (to reduce the traffic and maybe improve the speed). doing this you still have your object but with the binary data set to null...

anyway it is good that i can still get my data in some other way so...choosing the right and easiest way to retrive table data in nhibernate drives me mad somethimes :)

tnx
markov

You could mark that property as "lazy" and just not use it - it would not be filled until you access it.



I found that when I finally stopped thinking about tables and SQL and just thought in objects, using NH became infinitely easier. Your mileage may vary.

is that even possible in NHibernate?? I adapted the mapping xml:

<property column="content" type="Byte[]" name="Content" lazy="true" />

and have set the property to lazy but only got the following exception:

NHibernate.MappingException: Error reading resource: Application.Tables.
DocumentBinary.hbm.xml ---> NHibernate.MappingException: The 'lazy' attribute is not declared.

any idea?
tnx
markov

Sorry. I was still asleep when I wrote that.

I think the proper way is setting the class to be lazy but only make the properties you want to be lazy have the "virtual" modifier. So make only the byte[] property virtual. That's not a great solution, and I've never tried it myself, but it might work. :)