I have agenda items with a date, and want to group these agenda items by week number, derived from their date. The date corresponds to a field in the database, the derived week number is annoted @Transient.

The list method of my Criteria throws a QueryException: could not resolve property: week of my.package.Agenda. Is there anything specific to be configured for transient fields? What am I overlooking here?

Hi,

@Transient fields are not persisted into the database hence I believe you cannot use a criteria on this field. The sort by functionality tries to write a sql query adding a 'order by' clause. Ordering occurs in the db.

In your case I would recommend to have a look at the @Sort annotation together with a custom comparator.

Alternatively you could try using a SQL function. Provided that you have a function which returns the week number given the date it should work as well. See http://www.hibernate.org/hib_docs/v3/reference/en/html_single/#queryhql-ordering.

--Hardy

Correct me if I'm wrong, but I don't think I can use the sql date functions in criteria...

That will depend on your underlying database. If you db allows to have functions in the order by clause it should work.

You would have to give it a go.

--Hardy

I had already tried it without success. It looks like Hibernate only supports those constructs which are more or less standard sql, anything specific for the underlying database is not supported.

Hi,

I actually expected that Hibernate is passing the function call through without any modifications.

Have you tried to turn on sql debug trace? This way you can see which queries get executed against the db.

--Hardy

I don't think my criteria are translated into an sql query at all (Hibernate generates an error before actually accessing the database). I'll generate some more specific info, if you want...