Hibernate version: hibernate-2.1.4
Name and version of the database you are using: PostgreSQL 8.0b

I have searched hibernate documentations and faq's and this forum but still couldn't figure out how can (or if I can) use mathematical expressions in HQL select clause like it is done in SQL select clauses.

I want to make a query like this:

select (1/suggestion.numberOfAuthors) from Suggestion as suggestion

Is it possible, and how?

Thanks in advance.

Did you try it?

of course, i've tried, it didn't run giving:
aggregate function expected before ( in SELECT [select (1 / suggestion.numberOfAuthors) from ots.domain.Suggestion as suggestion]

when i change the query into this

select sum(1/suggestion.numberOfAuthors) from Suggestion as suggestion

it worked. in fact this was what i wanted. i was just trying withot aggregate functions before it gets too complicated.

now again there seems to be some problem with mathematical expressions in select clause. when i try to use a value that is returned by a subquery in select clause:

select sum(1.0 / (select size(suggestion2.authors) from Suggestion as suggestion2 where suggestion2=suggestion)), personnel.department from Suggestion as suggestion join suggestion.authors as suggestion_author join suggestion_author.personnel as personnel join personnel.department as dept group by dept

The error message given is:
net.sf.hibernate.QueryException: ( expected before ) in select [select sum(1.0 / (select ....

Probably not yet possible. The new Parser in H3 will improve a lot there, so if you can't get it to work, wait for some more advanced H3 versions.

The classic parser cannot deal with constants and cannot deal with expressions using operators in the select clause. H3's antler based parser will make this much easier to add in the future.